In my previous glider, I had a removable LiFePo battery that really worked out well (15Ah battery, ~0.95A typical panel draw). I typically flew 9-10hrs between charging it and would see a ~10Ah charge go back into it using a cheap Ah meter. I likedbeing able to bring it home and keep it in the recommended semi-discharged storage state until the next time I flew. The night before flying I would put it on the charger (in a large ceramic fire-safe flower pot) and it was ready the next morning to go
My new glider’s avionic battery is a 20Ah sealed lead acid type. It’s difficult to access under a cockpit floor panel and is not meant to be removed routinely so I have to charge it in-situ. My club’s gliderport doesn’t have power so I hadto install a solar panel tied directly to a charge controller at my shade hangar spot. When I park the glider, I plug it into the solar charger and leave it charging until my next flight. This is working ok because the battery is a sealed lead acid
I’d like to go back to a higher capacity LiFePo battery but I’m not sure how to manage the charging process. Assuming I have a proper solar charge controller setup that won’t confuse the battery’s built-in battery management system, I stillhave the issue of proper storage charge level. I don’t want a LiFePo battery sitting at full charge all the time (right?). My gliderport is 90mi from home and I usually arrive ~2hrs before flying. If I added an external battery bank on my solar
So, I currently have a simple charging setup with a SLA battery that is working but probably only has an effective 10Ah capacity. So far, this is seems adequate in conjunction with the glider’s small solar panels (they supply about 1A). And, to befair, I could switch over to the motor battery (another 20Ah SLA) late in a flight and maybe not eat much into its starting capability if I needed a save. I'm planning for 8+hr flights next season and would like more margin.
Going to LiFePo is going to make battery charging a lot more complicated – or is it? Am I being too concerned about having a LiFePo battery kept in a fully charged state? Any advice on how you or others are dealing with in-situ LiFePo charging? (yes, I’m worried about fires too)
Thx, JJ
Thinking you have a 31, do you have a third position forward of the spar?Yes, a 31. I don't currently have a 3rd position setup but it would be fairly easy to add one. It's certainly a worthwhile thought.
R
In my previous glider, I had a removable LiFePo battery that really worked out well (15Ah battery, ~0.95A typical panel draw). I typically flew 9-10hrs between charging it and would see a ~10Ah charge go back into it using a cheap Ah meter. I likedbeing able to bring it home and keep it in the recommended semi-discharged storage state until the next time I flew. The night before flying I would put it on the charger (in a large ceramic fire-safe flower pot) and it was ready the next morning to go
My new glider’s avionic battery is a 20Ah sealed lead acid type. It’s difficult to access under a cockpit floor panel and is not meant to be removed routinely so I have to charge it in-situ. My club’s gliderport doesn’t have power so I had toinstall a solar panel tied directly to a charge controller at my shade hangar spot. When I park the glider, I plug it into the solar charger and leave it charging until my next flight. This is working ok because the battery is a sealed lead acid type and
I’d like to go back to a higher capacity LiFePo battery but I’m not sure how to manage the charging process. Assuming I have a proper solar charge controller setup that won’t confuse the battery’s built-in battery management system, I stillhave the issue of proper storage charge level. I don’t want a LiFePo battery sitting at full charge all the time (right?). My gliderport is 90mi from home and I usually arrive ~2hrs before flying. If I added an external battery bank on my solar setup,
So, I currently have a simple charging setup with a SLA battery that is working but probably only has an effective 10Ah capacity. So far, this is seems adequate in conjunction with the glider’s small solar panels (they supply about 1A). And, to befair, I could switch over to the motor battery (another 20Ah SLA) late in a flight and maybe not eat much into its starting capability if I needed a save. I'm planning for 8+hr flights next season and would like more margin.
Going to LiFePo is going to make battery charging a lot more complicated – or is it? Am I being too concerned about having a LiFePo battery kept in a fully charged state? Any advice on how you or others are dealing with in-situ LiFePo charging? (yes,I’m worried about fires too)
Thx, JJI find the typical battery arrangement in the 26/31 inadequate for my needs for the reasons you state. I use a 12 AH LFP sitting on the baggage shelf, easily removed to home and charged however you think best. AS used to install the wiring for this in
My K2's have spent most of their life (since 2017) on the charger and
so far no issues. I've heard LiIon is best stored between 30 and 70%
charge, but for LiFe, the only story I've heard is that with age, they sometimes loose capacity and to fix it you need to leave them on the
charger for a week or so.
.... I would leave a properly set up LFP charger on the under-the-knees battery without much concern. Properly set up meaning CV charge at correct voltage followed by disconnect (no float).
On Friday, December 9, 2022 at 1:59:36 PM UTC-7, jfitch wrote:need. I'd like to think the motor battery can serve the backup role in the very rare event that actually becomes necessary.
.... I would leave a properly set up LFP charger on the under-the-knees battery without much concern. Properly set up meaning CV charge at correct voltage followed by disconnect (no float).
Thanks, this is good to hear. My friend's shut-off timer method sounds well-aligned.
Thinking about it, I would prefer to not add a 3rd battery. It's just one more system to maintain, test, pre-flight, etc. My strong preference is a primary avionic battery with a good manufacturer reputation and significantly more capacity than I
I guess that means my shade hangar solar system needs to get more complicated - but at least it stays on the ground.Some chargers discharge the battery when the AC is unplugged. Depending
thx, JJ
Some chargers discharge the battery when the AC is unplugged. Depending
on where you put the timer, you may want to verify the charger you have
is well behaved without AC.
In my previous glider, I had a removable LiFePo battery that really worked out well (15Ah battery, ~0.95A typical panel draw). I typically flew 9-10hrs between charging it and would see a ~10Ah charge go back into it using a cheap Ah meter. I likedbeing able to bring it home and keep it in the recommended semi-discharged storage state until the next time I flew. The night before flying I would put it on the charger (in a large ceramic fire-safe flower pot) and it was ready the next morning to go
My new glider’s avionic battery is a 20Ah sealed lead acid type. It’s difficult to access under a cockpit floor panel and is not meant to be removed routinely so I have to charge it in-situ. My club’s gliderport doesn’t have power so I had toinstall a solar panel tied directly to a charge controller at my shade hangar spot. When I park the glider, I plug it into the solar charger and leave it charging until my next flight. This is working ok because the battery is a sealed lead acid type and
I’d like to go back to a higher capacity LiFePo battery but I’m not sure how to manage the charging process. Assuming I have a proper solar charge controller setup that won’t confuse the battery’s built-in battery management system, I stillhave the issue of proper storage charge level. I don’t want a LiFePo battery sitting at full charge all the time (right?). My gliderport is 90mi from home and I usually arrive ~2hrs before flying. If I added an external battery bank on my solar setup,
So, I currently have a simple charging setup with a SLA battery that is working but probably only has an effective 10Ah capacity. So far, this is seems adequate in conjunction with the glider’s small solar panels (they supply about 1A). And, to befair, I could switch over to the motor battery (another 20Ah SLA) late in a flight and maybe not eat much into its starting capability if I needed a save. I'm planning for 8+hr flights next season and would like more margin.
Going to LiFePo is going to make battery charging a lot more complicated – or is it? Am I being too concerned about having a LiFePo battery kept in a fully charged state? Any advice on how you or others are dealing with in-situ LiFePo charging? (yes,I’m worried about fires too)
Thx, JJ
On Friday, December 9, 2022 at 11:36:07 AM UTC-8, John Johnson wrote:being able to bring it home and keep it in the recommended semi-discharged storage state until the next time I flew. The night before flying I would put it on the charger (in a large ceramic fire-safe flower pot) and it was ready the next morning to go
In my previous glider, I had a removable LiFePo battery that really worked out well (15Ah battery, ~0.95A typical panel draw). I typically flew 9-10hrs between charging it and would see a ~10Ah charge go back into it using a cheap Ah meter. I liked
install a solar panel tied directly to a charge controller at my shade hangar spot. When I park the glider, I plug it into the solar charger and leave it charging until my next flight. This is working ok because the battery is a sealed lead acid type andMy new glider’s avionic battery is a 20Ah sealed lead acid type. It’s difficult to access under a cockpit floor panel and is not meant to be removed routinely so I have to charge it in-situ. My club’s gliderport doesn’t have power so I had to
have the issue of proper storage charge level. I don’t want a LiFePo battery sitting at full charge all the time (right?). My gliderport is 90mi from home and I usually arrive ~2hrs before flying. If I added an external battery bank on my solar setup,I’d like to go back to a higher capacity LiFePo battery but I’m not sure how to manage the charging process. Assuming I have a proper solar charge controller setup that won’t confuse the battery’s built-in battery management system, I still
fair, I could switch over to the motor battery (another 20Ah SLA) late in a flight and maybe not eat much into its starting capability if I needed a save. I'm planning for 8+hr flights next season and would like more margin.So, I currently have a simple charging setup with a SLA battery that is working but probably only has an effective 10Ah capacity. So far, this is seems adequate in conjunction with the glider’s small solar panels (they supply about 1A). And, to be
yes, I’m worried about fires too)Going to LiFePo is going to make battery charging a lot more complicated – or is it? Am I being too concerned about having a LiFePo battery kept in a fully charged state? Any advice on how you or others are dealing with in-situ LiFePo charging? (
good idea because the X2 is VERY sensitive to input DC voltage and will prematurely terminate charging, again too late for you to do anything about it. The solar panels will replenish your donor battery while flying, so you will have plenty of energy toThx, JJI have the following setup for charging sans AC connection:
HiTec X2 AC/DC multi-chemistry charger
PowerSonic LFP 50 AHr donor battery
LFP solar charge controller
50W solar panels (2)
This setup guarantees that the donor battery will not go flat while charging (which you won't find out about until you get to the field, depriving you of adequate time to charge your avionics battery in time). Using PbS batteries as the donor isn't a
Granted, this won't leave much change out of a $1k bill, but it won't leave you high and dry on a beautiful flying day.
Tom
On Friday, December 9, 2022 at 11:36:07 AM UTC-8, John Johnson wrote:...
I’m worried about fires too)
Going to LiFePo is going to make battery charging a lot more complicated – or is it? Am I being too concerned about having a LiFePo battery kept in a fully charged state? Any advice on how you or others are dealing with in-situ LiFePo charging? (yes,
good idea because the X2 is VERY sensitive to input DC voltage and will prematurely terminate charging, again too late for you to do anything about it. The solar panels will replenish your donor battery while flying, so you will have plenty of energy to
Thx, JJ
I have the following setup for charging sans AC connection:
HiTec X2 AC/DC multi-chemistry charger
PowerSonic LFP 50 AHr donor battery
LFP solar charge controller
50W solar panels (2)
This setup guarantees that the donor battery will not go flat while charging (which you won't find out about until you get to the field, depriving you of adequate time to charge your avionics battery in time). Using PbS batteries as the donor isn't a
Granted, this won't leave much change out of a $1k bill, but it won't leave you high and dry on a beautiful flying day.I use the same system as Tom, but a different selection of components leaves most of a $1k
Tom
I have the following setup for charging sans AC connection:
HiTec X2 AC/DC multi-chemistry charger. Tom
PowerSonic LFP 50 AHr donor battery
LFP solar charge controller
50W solar panels (2)
I use the same system as Tom, but a different selection of components leaves most of a $1k
bill (prices from Amazon), and has been sufficient for years with a panel drawing 1.5A
from a 20AH LiFePO4 battery. I typically fly about 6 hours, never more than 8.
$35 ISDT Q6 Nano Lipo Battery DC-DC Charger/Discharger,
$70 Miady 12V 16Ah Deep Cycle LiFePO4 Battery
$21 ExpertPower 10A 12/24V Intelligent PWM Solar Charge Controller
$58 HQST 50W 12V Polycrystalline Solar Panel
$184 Total
already). I'll research a LFP donor battery and decide if I'm sticking with a DC-DC setup or adding an inverter. Since the solution will be bundled for going with me on Safaris, I'm leaning toward the extra capability an inverter setup will provide. I'llI have the following setup for charging sans AC connection:
HiTec X2 AC/DC multi-chemistry charger. Tom
PowerSonic LFP 50 AHr donor battery
LFP solar charge controller
50W solar panels (2)
I use the same system as Tom, but a different selection of components leaves most of a $1k
bill (prices from Amazon), and has been sufficient for years with a panel drawing 1.5A
from a 20AH LiFePO4 battery. I typically fly about 6 hours, never more than 8.
$35 ISDT Q6 Nano Lipo Battery DC-DC Charger/Discharger,
$70 Miady 12V 16Ah Deep Cycle LiFePO4 Battery
$21 ExpertPower 10A 12/24V Intelligent PWM Solar Charge Controller
$58 HQST 50W 12V Polycrystalline Solar Panel
$184 TotalTom, Eric, thanks for providing your examples. I currently have a 150W panel and charge controller that I'm directly connecting, in turn, to each of my -VRLA- batteries for charging (find the engine battery is always close to being fully charged
Great information from everyone - appreciate it. I feel confident now to proceed with a LFP avionic battery while keeping my engine battery as-is (VRLA).
thanks, JJ
On Saturday, December 10, 2022 at 10:49:27 AM UTC-8, John Johnson wrote:already). I'll research a LFP donor battery and decide if I'm sticking with a DC-DC setup or adding an inverter. Since the solution will be bundled for going with me on Safaris, I'm leaning toward the extra capability an inverter setup will provide. I'll
I have the following setup for charging sans AC connection:
HiTec X2 AC/DC multi-chemistry charger. Tom
PowerSonic LFP 50 AHr donor battery
LFP solar charge controller
50W solar panels (2)
I use the same system as Tom, but a different selection of components leaves most of a $1k
bill (prices from Amazon), and has been sufficient for years with a panel drawing 1.5A
from a 20AH LiFePO4 battery. I typically fly about 6 hours, never more than 8.
$35 ISDT Q6 Nano Lipo Battery DC-DC Charger/Discharger,
$70 Miady 12V 16Ah Deep Cycle LiFePO4 Battery
$21 ExpertPower 10A 12/24V Intelligent PWM Solar Charge Controller
$58 HQST 50W 12V Polycrystalline Solar Panel
$184 TotalTom, Eric, thanks for providing your examples. I currently have a 150W panel and charge controller that I'm directly connecting, in turn, to each of my -VRLA- batteries for charging (find the engine battery is always close to being fully charged
double the size of the charging battery. On the other hand, if you don't care if the system works and you are left high and dry when it's time to go fly, then go cheap on the donor battery.Great information from everyone - appreciate it. I feel confident now to proceed with a LFP avionic battery while keeping my engine battery as-is (VRLA).
thanks, JJEric's solution has one major problem: he is using a 16AH battery to recharge a 20AH battery. This, simply, DOES NOT WORK! Believe me, I have tried that option and it FAILED! If you want a fool-proof solution the donor battery needs to be roughly
Tom
On Sunday, December 11, 2022 at 11:25:02 PM UTC-8, 2G wrote:already). I'll research a LFP donor battery and decide if I'm sticking with a DC-DC setup or adding an inverter. Since the solution will be bundled for going with me on Safaris, I'm leaning toward the extra capability an inverter setup will provide. I'll
On Saturday, December 10, 2022 at 10:49:27 AM UTC-8, John Johnson wrote: >>>>> I have the following setup for charging sans AC connection:
Tom, Eric, thanks for providing your examples. I currently have a 150W panel and charge controller that I'm directly connecting, in turn, to each of my -VRLA- batteries for charging (find the engine battery is always close to being fully charged. Tom
HiTec X2 AC/DC multi-chemistry charger
PowerSonic LFP 50 AHr donor battery
LFP solar charge controller
50W solar panels (2)
I use the same system as Tom, but a different selection of components leaves most of a $1k
bill (prices from Amazon), and has been sufficient for years with a panel drawing 1.5A
from a 20AH LiFePO4 battery. I typically fly about 6 hours, never more than 8.
$35 ISDT Q6 Nano Lipo Battery DC-DC Charger/Discharger,
$70 Miady 12V 16Ah Deep Cycle LiFePO4 Battery
$21 ExpertPower 10A 12/24V Intelligent PWM Solar Charge Controller
$58 HQST 50W 12V Polycrystalline Solar Panel
$184 Total
double the size of the charging battery. On the other hand, if you don't care if the system works and you are left high and dry when it's time to go fly, then go cheap on the donor battery.Eric's solution has one major problem: he is using a 16AH battery to recharge a 20AH battery. This, simply, DOES NOT WORK! Believe me, I have tried that option and it FAILED! If you want a fool-proof solution the donor battery needs to be roughly
Great information from everyone - appreciate it. I feel confident now to proceed with a LFP avionic battery while keeping my engine battery as-is (VRLA).
thanks, JJ
deliver 8.3A; I have NEVER seen 8.3A and am satisfied if they deliver HALF of that (and you get nothing if the Sun is blocked). And that is at the best time of day, dropping off before and after noon. By over-sizing the panels I know that I can recharge
Tom
I will add that the same goes for under sizing the wattage of the solar panels. Solar panels NEVER deliver the nameplate wattage since that is only possible at noon at the equator with the panels pointed DIRECTLY at the Sun. My two 50W panels SHOULD
Eric's solution has one major problem: he is using a 16AH battery to recharge a 20AH battery. This, simply, DOES NOT WORK! Believe me, I have tried that option and it FAILED! If you want a fool-proof solution the donor battery needs to be roughlydouble the size of the charging battery. On the other hand, if you don't care if the system works and you are left high and dry when it's time to go fly, then go cheap on the donor battery.
TomThis opinion is incorrect.
I don’t see the need to lug around solar panels unless you’re camping out and eating squirrels.R, thanks for getting me to re-think the safari charging situation. Was thinking I would need to plug the donor into a charger right after disconnecting from the glider in the morning (solar panel mounted to the trailer). Depending on the field, it
Must be a ‘out west’ thing…brownouts and rolling power interruptions. We have plenty of A/C power in the east.
One battery, two chargers. I picked a Lithium as my power supply (donor) because of its light weight and life span.
Since I race, I have a 3rd 10ah for redundancy.
I have a hard time understanding how a lower ah battery can charge a higher one to full capacity. Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line of thinking?
Then again, ‘out west’.
R
On Monday, December 12, 2022 at 10:34:51 AM UTC-7, R wrote:may not be easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah LFP donor, I could get 4-5 glider charges out of it before taking it off-field for recharging overnight before a rest day.
I don’t see the need to lug around solar panels unless you’re camping out and eating squirrels.R, thanks for getting me to re-think the safari charging situation. Was thinking I would need to plug the donor into a charger right after disconnecting from the glider in the morning (solar panel mounted to the trailer). Depending on the field, it
Must be a ‘out west’ thing…brownouts and rolling power interruptions. >> We have plenty of A/C power in the east.
One battery, two chargers. I picked a Lithium as my power supply (donor) because of its light weight and life span.
Since I race, I have a 3rd 10ah for redundancy.
I have a hard time understanding how a lower ah battery can charge a higher one to full capacity. Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line of thinking?
Then again, ‘out west’.
R
thx, JJ
On Monday, December 12, 2022 at 10:34:51 AM UTC-7, R wrote:may not be easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah LFP donor, I could get 4-5 glider charges out of it before taking it off-field for recharging overnight before a rest day.
I don’t see the need to lug around solar panels unless you’re camping out and eating squirrels.R, thanks for getting me to re-think the safari charging situation. Was thinking I would need to plug the donor into a charger right after disconnecting from the glider in the morning (solar panel mounted to the trailer). Depending on the field, it
Must be a ‘out west’ thing…brownouts and rolling power interruptions. >> We have plenty of A/C power in the east.
One battery, two chargers. I picked a Lithium as my power supply (donor) because of its light weight and life span.
Since I race, I have a 3rd 10ah for redundancy.
I have a hard time understanding how a lower ah battery can charge a higher one to full capacity. Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line of thinking?
Then again, ‘out west’.
R
thx, JJIf you are driving your tow vehicle every day or two, you can use it's battery to charge
I have a hard time understanding how a lower ah battery can charge a higher one to full capacity. Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line of thinking?
Instead of all of these complex systems, panels, controllers, etc., I just bough an
inverter at Amazon and can charge my batteries in the evening/morning in the car or simply
leave it plugged in and forget it until the next flight. Considerably less expensive, too...
https://smile.amazon.com/gp/product/B004MDXS0U/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Dan
5J
On 12/12/22 11:49, John Johnson wrote:
On Monday, December 12, 2022 at 10:34:51 AM UTC-7, R wrote:
I don’t see the need to lug around solar panels unless you’re camping out and eatingR, thanks for getting me to re-think the safari charging situation. Was thinking I
squirrels.
Must be a ‘out west’ thing…brownouts and rolling power interruptions. >>> We have plenty of A/C power in the east.
One battery, two chargers. I picked a Lithium as my power supply (donor) because of its
light weight and life span.
Since I race, I have a 3rd 10ah for redundancy.
I have a hard time understanding how a lower ah battery can charge a higher one to full
capacity. Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line
of thinking?
Then again, ‘out west’.
R
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line of thinking?
On 12/12/2022 12:34 PM, R wrote:
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything
free’ line of thinking?
Any day now Henry! https://www.reuters.com/business/energy/us-announce-scientific-breakthrough-fusion-energy-sources-2022-12-12/
On 12/11/2022 11:36 PM, 2G wrote:already). I'll research a LFP donor battery and decide if I'm sticking with a DC-DC setup or adding an inverter. Since the solution will be bundled for going with me on Safaris, I'm leaning toward the extra capability an inverter setup will provide. I'll
On Sunday, December 11, 2022 at 11:25:02 PM UTC-8, 2G wrote:
On Saturday, December 10, 2022 at 10:49:27 AM UTC-8, John Johnson wrote: >>>>> I have the following setup for charging sans AC connection:
Tom, Eric, thanks for providing your examples. I currently have a 150W panel and charge controller that I'm directly connecting, in turn, to each of my -VRLA- batteries for charging (find the engine battery is always close to being fully charged. Tom
HiTec X2 AC/DC multi-chemistry charger
PowerSonic LFP 50 AHr donor battery
LFP solar charge controller
50W solar panels (2)
I use the same system as Tom, but a different selection of components leaves most of a $1k
bill (prices from Amazon), and has been sufficient for years with a panel drawing 1.5A
from a 20AH LiFePO4 battery. I typically fly about 6 hours, never more than 8.
$35 ISDT Q6 Nano Lipo Battery DC-DC Charger/Discharger,
$70 Miady 12V 16Ah Deep Cycle LiFePO4 Battery
$21 ExpertPower 10A 12/24V Intelligent PWM Solar Charge Controller
$58 HQST 50W 12V Polycrystalline Solar Panel
$184 Total
double the size of the charging battery. On the other hand, if you don't care if the system works and you are left high and dry when it's time to go fly, then go cheap on the donor battery.Eric's solution has one major problem: he is using a 16AH battery to recharge a 20AH battery. This, simply, DOES NOT WORK! Believe me, I have tried that option and it FAILED! If you want a fool-proof solution the donor battery needs to be roughly
Great information from everyone - appreciate it. I feel confident now to proceed with a LFP avionic battery while keeping my engine battery as-is (VRLA).
thanks, JJ
deliver 8.3A; I have NEVER seen 8.3A and am satisfied if they deliver HALF of that (and you get nothing if the Sun is blocked). And that is at the best time of day, dropping off before and after noon. By over-sizing the panels I know that I can recharge
Tom
I will add that the same goes for under sizing the wattage of the solar panels. Solar panels NEVER deliver the nameplate wattage since that is only possible at noon at the equator with the panels pointed DIRECTLY at the Sun. My two 50W panels SHOULD
My situation is not as dire as Tom suggests, for several reasons
* my longest flights (8 hours) only require the 16AH donor battery to replace 12 AH
* I put the donor battery on charge by 8am, so it has almost 12 hours to recover
* I can also charge the glider from my tow vehicle battery using the same DC-DC charger
Generally, if there is enough sun to make the thermals we need, there is enough sun to
fully charge the donor battery. I've only had to use the vehicle once in the 10 or so
years I've been doing this. It can easily charge the glider at 4A (max glider battery
charge rate) and still be ready to fly as usual. Also, there is an option to solar
charging: put the donor battery on charge at some place on the field that has AC power.
That's an option everywhere I fly, or use your tow vehicle battery to power the DC-DC charger.
I'm a minimalist, Tom's a maximalist: pick a point on the spectrum between us that
satisfies your requirements.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
On 12/12/2022 5:08 PM, Dave Nadler wrote:
On 12/12/2022 12:34 PM, R wrote:
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything
free’ line of thinking?
Any day now Henry!
https://www.reuters.com/business/energy/us-announce-scientific-breakthrough-fusion-energy-sources-2022-12-12/
"Fusion is the energy source of the future, and always will be!"
Yeh….I remember ‘Fusion’ from the ‘60s. It’s right up there with Quantum Computing, Cryptocurrency, sending humans to Mars, and Carbon Credits.Better be careful R, with these kind of comments you may be ban from Twitter and Facebook. OBTP
Chernobyl
LALA Land
FTX
Cancer
Liberal Europeans smoking weed.
R
This looks a like a better description than Quora:
https://www.pppl.gov/news/2021/10-facts-you-should-know-about-fusion-energy
Fusion will be a great way to charge LiFePO batteries! Don't sell your
solar panels just yet...
Eric
On 12/13/2022 10:16 AM, Dan Marotta wrote:
I was curious about the by-products of fusion reactions and came
across the following discussion. Pretty interesting.
https://www.quora.com/What-would-be-the-by-products-of-Nuclear-Fusion?share=1
Dan
5J
On 12/12/22 18:04, Moshe Braner wrote:
On 12/12/2022 5:08 PM, Dave Nadler wrote:
On 12/12/2022 12:34 PM, R wrote:
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything
free’ line of thinking?
Any day now Henry!
https://www.reuters.com/business/energy/us-announce-scientific-breakthrough-fusion-energy-sources-2022-12-12/
"Fusion is the energy source of the future, and always will be!"
I was curious about the by-products of fusion reactions and came across the following
discussion. Pretty interesting.
https://www.quora.com/What-would-be-the-by-products-of-Nuclear-Fusion?share=1
Dan
5J
On 12/12/22 18:04, Moshe Braner wrote:
On 12/12/2022 5:08 PM, Dave Nadler wrote:
On 12/12/2022 12:34 PM, R wrote:
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line of thinking?
Any day now Henry!
https://www.reuters.com/business/energy/us-announce-scientific-breakthrough-fusion-energy-sources-2022-12-12/
"Fusion is the energy source of the future, and always will be!"
This looks a like a better description than Quora:Eric, don't get too excited about this breakthrough in Fusion Energy. The primary concept of making Fusion Power is through heat developed by lasers, maintaining that heat requires power and a huge amount at that. Just recently the Liverpool lab
https://www.pppl.gov/news/2021/10-facts-you-should-know-about-fusion-energy
Fusion will be a great way to charge LiFePO batteries! Don't sell your solar panels just
yet...
Eric
On 12/13/2022 10:16 AM, Dan Marotta wrote:
I was curious about the by-products of fusion reactions and came across the following
discussion. Pretty interesting.
https://www.quora.com/What-would-be-the-by-products-of-Nuclear-Fusion?share=1
Dan
5J
On 12/12/22 18:04, Moshe Braner wrote:--
On 12/12/2022 5:08 PM, Dave Nadler wrote:
On 12/12/2022 12:34 PM, R wrote:
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line of thinking?
Any day now Henry!
https://www.reuters.com/business/energy/us-announce-scientific-breakthrough-fusion-energy-sources-2022-12-12/
"Fusion is the energy source of the future, and always will be!"
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
I was curious about the by-products of fusion reactions and came acrossshare=1
the following discussion. Pretty interesting.
https://www.quora.com/What-would-be-the-by-products-of-Nuclear-Fusion?
On Tuesday, December 13, 2022 at 2:36:44 PM UTC-5, Eric Greenwell wrote:produced 10 quadrillion units of power from this concept, yet they did tell us the real story.
This looks a like a better description than Quora:Eric, don't get too excited about this breakthrough in Fusion Energy. The primary concept of making Fusion Power is through heat developed by lasers, maintaining that heat requires power and a huge amount at that. Just recently the Liverpool lab
https://www.pppl.gov/news/2021/10-facts-you-should-know-about-fusion-energy >>
Fusion will be a great way to charge LiFePO batteries! Don't sell your solar panels just
yet...
Eric
On 12/13/2022 10:16 AM, Dan Marotta wrote:
I was curious about the by-products of fusion reactions and came across the following--
discussion. Pretty interesting.
https://www.quora.com/What-would-be-the-by-products-of-Nuclear-Fusion?share=1
Dan
5J
On 12/12/22 18:04, Moshe Braner wrote:
On 12/12/2022 5:08 PM, Dave Nadler wrote:
On 12/12/2022 12:34 PM, R wrote:
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line of thinking?
Any day now Henry!
https://www.reuters.com/business/energy/us-announce-scientific-breakthrough-fusion-energy-sources-2022-12-12/
"Fusion is the energy source of the future, and always will be!"
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
I work with lasers more often than you think, they are impressive and dangerous as well, Fusion has a long way to go, yet breakthroughs are advancing, just not as rapidly as FTX and Enron. Old Bob, The Purist
On 12/12/2022 5:08 PM, Dave Nadler wrote:
On 12/12/2022 12:34 PM, R wrote:"Fusion is the energy source of the future, and always will be!"
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything
free’ line of thinking?
Any day now Henry!
https://www.reuters.com/business/energy/us-announce-scientific- breakthrough-fusion-energy-sources-2022-12-12/
On Monday, December 12, 2022 at 6:39:15 AM UTC-8, Eric Greenwell wrote:already). I'll research a LFP donor battery and decide if I'm sticking with a DC-DC setup or adding an inverter. Since the solution will be bundled for going with me on Safaris, I'm leaning toward the extra capability an inverter setup will provide. I'll
On 12/11/2022 11:36 PM, 2G wrote:
On Sunday, December 11, 2022 at 11:25:02 PM UTC-8, 2G wrote:
On Saturday, December 10, 2022 at 10:49:27 AM UTC-8, John Johnson wrote: >>>>>>> I have the following setup for charging sans AC connection:
Tom, Eric, thanks for providing your examples. I currently have a 150W panel and charge controller that I'm directly connecting, in turn, to each of my -VRLA- batteries for charging (find the engine battery is always close to being fully charged. Tom
HiTec X2 AC/DC multi-chemistry charger
PowerSonic LFP 50 AHr donor battery
LFP solar charge controller
50W solar panels (2)
I use the same system as Tom, but a different selection of components leaves most of a $1k
bill (prices from Amazon), and has been sufficient for years with a panel drawing 1.5A
from a 20AH LiFePO4 battery. I typically fly about 6 hours, never more than 8.
$35 ISDT Q6 Nano Lipo Battery DC-DC Charger/Discharger,
$70 Miady 12V 16Ah Deep Cycle LiFePO4 Battery
$21 ExpertPower 10A 12/24V Intelligent PWM Solar Charge Controller >>>>>> $58 HQST 50W 12V Polycrystalline Solar Panel
$184 Total
double the size of the charging battery. On the other hand, if you don't care if the system works and you are left high and dry when it's time to go fly, then go cheap on the donor battery.Eric's solution has one major problem: he is using a 16AH battery to recharge a 20AH battery. This, simply, DOES NOT WORK! Believe me, I have tried that option and it FAILED! If you want a fool-proof solution the donor battery needs to be roughly
Great information from everyone - appreciate it. I feel confident now to proceed with a LFP avionic battery while keeping my engine battery as-is (VRLA).
thanks, JJ
deliver 8.3A; I have NEVER seen 8.3A and am satisfied if they deliver HALF of that (and you get nothing if the Sun is blocked). And that is at the best time of day, dropping off before and after noon. By over-sizing the panels I know that I can recharge
Tom
I will add that the same goes for under sizing the wattage of the solar panels. Solar panels NEVER deliver the nameplate wattage since that is only possible at noon at the equator with the panels pointed DIRECTLY at the Sun. My two 50W panels SHOULD
little in the morning and late afternoon. My panel draws typically 2 A, so an 8 hour flight needs 16 AHr. The entire system may be 60 to 70% efficient given all of the power conversions (I have not actually measured this as my solution is over-kill), soMy situation is not as dire as Tom suggests, for several reasons
* my longest flights (8 hours) only require the 16AH donor battery to replace 12 AH
* I put the donor battery on charge by 8am, so it has almost 12 hours to recover
* I can also charge the glider from my tow vehicle battery using the same DC-DC charger
Generally, if there is enough sun to make the thermals we need, there is enough sun to
fully charge the donor battery. I've only had to use the vehicle once in the 10 or so
years I've been doing this. It can easily charge the glider at 4A (max glider battery
charge rate) and still be ready to fly as usual. Also, there is an option to solar
charging: put the donor battery on charge at some place on the field that has AC power.
That's an option everywhere I fly, or use your tow vehicle battery to power the DC-DC charger.
I'm a minimalist, Tom's a maximalist: pick a point on the spectrum between us that
satisfies your requirements.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
You have seriously degraded you whole system by not using an MPPT (maximum power point tracking) solar charger. A PWM charger will deliver less than half the energy than an MPPT charger. Charging energy varies like a half sine wave, so there is very
This is also why it is MANDATORY that you actually measure the power consumption of your panel, preferably in flight. The largest consumer is my flight computer, the LX9070, which draws around 0.75 A (depends on display brightness). I also have abackup glide computer/vario, the S100, which draws around 0.3 A. Now add a radio, transponder with ADSB/Out, S10 vario, and a Garmin G5 primary flight display and you are up to 2 A.
Pilots that have less energy needs, current and/or time, can size their charging systems accordingly.your charging deficit is).
I went to this after having flights cut short because the battery wasn't fully charged prior to flight, a real PITA. I guess that fits perfectly into Eric's minimalist outlook.
Tom
PS I use the display of the X2 to show me the AHr delivered and double-check that with an inline battery charging monitor (if the X2 has a fault at any time like due to low input DC voltage, the AHr delivered display is gone and you don't know what
Am I being too concerned about having a LiFePo battery kept in a fully charged state? Any advice on how you or others are dealing with in-situ LiFePo charging? (yes, I’m worried about fires too)
The people most attracted to these methods can not easily remove their batteries from theEric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much more convenient
glider, which includes every Schleicher self-launcher, and perhaps all the DG
self-launchers, too. If the battery can be removed, most pilots just take it home with
them. I wish I could do that, but removing and replacing the avionics battery is a 40
minute process. The typical engine run is enough for the alternator to keep the starter
battery charged, so it rarely needs external charging (Schleicher gliders, anyway)
On 12/12/2022 11:04 AM, Dan Marotta wrote:
Instead of all of these complex systems, panels, controllers, etc., I just bough an
inverter at Amazon and can charge my batteries in the evening/morning in the car or simply
leave it plugged in and forget it until the next flight. Considerably less expensive, too...
https://smile.amazon.com/gp/product/B004MDXS0U/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Dan
5J
On 12/12/22 11:49, John Johnson wrote:--
On Monday, December 12, 2022 at 10:34:51 AM UTC-7, R wrote:
I don’t see the need to lug around solar panels unless you’re camping out and eatingR, thanks for getting me to re-think the safari charging situation. Was thinking I
squirrels.
Must be a ‘out west’ thing…brownouts and rolling power interruptions.
We have plenty of A/C power in the east.
One battery, two chargers. I picked a Lithium as my power supply (donor) because of its
light weight and life span.
Since I race, I have a 3rd 10ah for redundancy.
I have a hard time understanding how a lower ah battery can charge a higher one to full
capacity. Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything free’ line
of thinking?
Then again, ‘out west’.
R
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
On 12/13/22 12:26 AM, 2G wrote:already). I'll research a LFP donor battery and decide if I'm sticking with a DC-DC setup or adding an inverter. Since the solution will be bundled for going with me on Safaris, I'm leaning toward the extra capability an inverter setup will provide. I'll
On Monday, December 12, 2022 at 6:39:15 AM UTC-8, Eric Greenwell wrote:
On 12/11/2022 11:36 PM, 2G wrote:
On Sunday, December 11, 2022 at 11:25:02 PM UTC-8, 2G wrote:
On Saturday, December 10, 2022 at 10:49:27 AM UTC-8, John Johnson wrote:
Tom, Eric, thanks for providing your examples. I currently have a 150W panel and charge controller that I'm directly connecting, in turn, to each of my -VRLA- batteries for charging (find the engine battery is always close to being fully chargedI have the following setup for charging sans AC connection:. Tom
HiTec X2 AC/DC multi-chemistry charger
PowerSonic LFP 50 AHr donor battery
LFP solar charge controller
50W solar panels (2)
I use the same system as Tom, but a different selection of components leaves most of a $1k
bill (prices from Amazon), and has been sufficient for years with a panel drawing 1.5A
from a 20AH LiFePO4 battery. I typically fly about 6 hours, never more than 8.
$35 ISDT Q6 Nano Lipo Battery DC-DC Charger/Discharger,
$70 Miady 12V 16Ah Deep Cycle LiFePO4 Battery
$21 ExpertPower 10A 12/24V Intelligent PWM Solar Charge Controller >>>>>> $58 HQST 50W 12V Polycrystalline Solar Panel
$184 Total
double the size of the charging battery. On the other hand, if you don't care if the system works and you are left high and dry when it's time to go fly, then go cheap on the donor battery.Eric's solution has one major problem: he is using a 16AH battery to recharge a 20AH battery. This, simply, DOES NOT WORK! Believe me, I have tried that option and it FAILED! If you want a fool-proof solution the donor battery needs to be roughly
Great information from everyone - appreciate it. I feel confident now to proceed with a LFP avionic battery while keeping my engine battery as-is (VRLA).
thanks, JJ
SHOULD deliver 8.3A; I have NEVER seen 8.3A and am satisfied if they deliver HALF of that (and you get nothing if the Sun is blocked). And that is at the best time of day, dropping off before and after noon. By over-sizing the panels I know that I can
Tom
I will add that the same goes for under sizing the wattage of the solar panels. Solar panels NEVER deliver the nameplate wattage since that is only possible at noon at the equator with the panels pointed DIRECTLY at the Sun. My two 50W panels
little in the morning and late afternoon. My panel draws typically 2 A, so an 8 hour flight needs 16 AHr. The entire system may be 60 to 70% efficient given all of the power conversions (I have not actually measured this as my solution is over-kill), soMy situation is not as dire as Tom suggests, for several reasons
* my longest flights (8 hours) only require the 16AH donor battery to replace 12 AH
* I put the donor battery on charge by 8am, so it has almost 12 hours to recover
* I can also charge the glider from my tow vehicle battery using the same DC-DC charger
Generally, if there is enough sun to make the thermals we need, there is enough sun to
fully charge the donor battery. I've only had to use the vehicle once in the 10 or so
years I've been doing this. It can easily charge the glider at 4A (max glider battery
charge rate) and still be ready to fly as usual. Also, there is an option to solar
charging: put the donor battery on charge at some place on the field that has AC power.
That's an option everywhere I fly, or use your tow vehicle battery to power the DC-DC charger.
I'm a minimalist, Tom's a maximalist: pick a point on the spectrum between us that
satisfies your requirements.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
You have seriously degraded you whole system by not using an MPPT (maximum power point tracking) solar charger. A PWM charger will deliver less than half the energy than an MPPT charger. Charging energy varies like a half sine wave, so there is very
backup glide computer/vario, the S100, which draws around 0.3 A. Now add a radio, transponder with ADSB/Out, S10 vario, and a Garmin G5 primary flight display and you are up to 2 A.This is also why it is MANDATORY that you actually measure the power consumption of your panel, preferably in flight. The largest consumer is my flight computer, the LX9070, which draws around 0.75 A (depends on display brightness). I also have a
your charging deficit is).Pilots that have less energy needs, current and/or time, can size their charging systems accordingly.
I went to this after having flights cut short because the battery wasn't fully charged prior to flight, a real PITA. I guess that fits perfectly into Eric's minimalist outlook.
Tom
PS I use the display of the X2 to show me the AHr delivered and double-check that with an inline battery charging monitor (if the X2 has a fault at any time like due to low input DC voltage, the AHr delivered display is gone and you don't know what
Gosh, with all those hardware and energy management issues to deal with, maybe you should take a flight engineer with you? Give you more time to
look outside.
I'm a big fan of just using a properly sized battery, making sure it's charged, and then go fly. I'll look at the panel voltage occasionally, sometimes look at the voltage drop when transmitting on the radio, but
don't really obsess about it. In 14 years of flying, never lost power
to the panel, or had a battery related failure to start the engine.
I've done 8 hr flights, but frankly don't enjoy that anymore.
My situation is very similar to the OP, a Schleicher motorglider with
the two large 20 AH batteries. He says 1.6 amp panel draw, with an amp supplied by the solar panels. So eight hour flights times .6 amp is 4.8
AH according to my calculations. He has a 20 AH battery, and could
easily tap into another 20 AH, and has decided he needs "more margin". Really? He has seen no problems with the current setup, and the math
doesn't begin to show a potential problem, but he has to "upgrade" from
20 AH to a 15 AH lithium basttery. Why? Because LITHIUM!!!
Sounds like he's going way out of his way, complicating his charging requirements, in order to justify that change. Golly gee, we've never
seen that before, have we? Certainly not on R.A.S.!!!
Dave
On Mon, 12 Dec 2022 20:04:15 -0500, Moshe Braner wrote:
On 12/12/2022 5:08 PM, Dave Nadler wrote:Nice quote!
On 12/12/2022 12:34 PM, R wrote:"Fusion is the energy source of the future, and always will be!"
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything
free’ line of thinking?
Any day now Henry!
https://www.reuters.com/business/energy/us-announce-scientific- breakthrough-fusion-energy-sources-2022-12-12/
Here's another good write up in the recent fusion test shot@ worth a read,
I think.
https://arstechnica.com/science/2022/12/what-enabled-the-big-boost-in- fusion-energy-announced-this-week/
--
Martin | martin at
Gregorie | gregorie dot org
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of a problem withEric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much more convenient--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
On Tuesday, December 13, 2022 at 4:28:02 PM UTC-8, Martin Gregorie
wrote:
On Mon, 12 Dec 2022 20:04:15 -0500, Moshe Braner wrote:
On 12/12/2022 5:08 PM, Dave Nadler wrote:breakthrough-fusion-energy-sources-2022-12-12/
On 12/12/2022 12:34 PM, R wrote:
Isn’t that in the ‘perpetual motion’ ‘fusion’ ‘I want everything
free’ line of thinking?
Any day now Henry!
https://www.reuters.com/business/energy/us-announce-scientific-
Nice quote!"Fusion is the energy source of the future, and always will be!"
Here's another good write up in the recent fusion test shot@ worth a
read,
I think.
https://arstechnica.com/science/2022/12/what-enabled-the-big-boost-in-
fusion-energy-announced-this-week/
--
Martin | martin at Gregorie | gregorie dot org
I wouldn't get too excited about fusion yet: the experiment produced
enough energy to power a Tesla for about one mile (305 WHr). And if you compare the cost to produce that energy vs what it costs off of the grid
you would be massively disappointed. The main point was that they were
able to have a net power output, a first for fusion research.
Tom
On 12/14/2022 8:29 AM, jfitch wrote:than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of a problem with
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much more convenient--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
I didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that under clouds (by
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:convenient than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of a
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much more--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to align and plug in theI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that under clouds (by
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
Going to LiFePo is going to make battery charging a lot more complicated – or is it? Am I being too concerned about having a LiFePo battery kept in a fully charged state?
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of a problem with
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much more convenient--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to align and plug in theI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that under clouds (by
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
The only advantage over the equivalent LFP (like the Power-Sonic PSL-BTP-12200) appears toGoing to LiFePo is going to make battery charging a lot more complicated – or is it? Am I being too concerned about having a LiFePo battery kept in a fully charged state?
I've had 2x LiFePo4 15Ah batteries for 6 years now.
I always keep them on the charger during the flying season. I keep them off the charger during winter, except for a charge every month or so...
I test their capacity every year. This year, after 6 years they are both still at 92% of their nominal capacity.
So Id' say...don't worry too much, it's fine to keep the batteries on the charger !
If I had to change batteries now, I'd go for NMC batteries though: https://www.gliderpilotshop.com/nmc-12-20-14-4v-20ah.html
Regards
Ludovic
On Wednesday, December 14, 2022 at 10:19:44 PM UTC-8, jfitch wrote:convenient than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of a
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much more--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
by actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to align and plug inI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that under clouds (
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
The connector is not the issue: it is the battery tie-downs that take the time. I decided that the $2,800 solar panel equals a $100 battery - if it is working.I'd certainly agree that the panels sourced from AS are not cost effective. I got mine essentially free, and they do provide some useful charge. It takes very little to hold a 12 or even 16AH LFP in place. A simple tray with a strap over the top is all
On Wednesday, December 14, 2022 at 11:17:26 PM UTC-8, 2G wrote:convenient than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of a
On Wednesday, December 14, 2022 at 10:19:44 PM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much more--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
by actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to align and plug inI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that under clouds (
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
that is necessary.The connector is not the issue: it is the battery tie-downs that take the time. I decided that the $2,800 solar panel equals a $100 battery - if it is working.I'd certainly agree that the panels sourced from AS are not cost effective. I got mine essentially free, and they do provide some useful charge. It takes very little to hold a 12 or even 16AH LFP in place. A simple tray with a strap over the top is all
On Thursday, December 15, 2022 at 8:45:35 AM UTC-8, jfitch wrote:convenient than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of a
On Wednesday, December 14, 2022 at 11:17:26 PM UTC-8, 2G wrote:
On Wednesday, December 14, 2022 at 10:19:44 PM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much more--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
clouds (by actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to align andI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that under
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
all that is necessary.The connector is not the issue: it is the battery tie-downs that take the time. I decided that the $2,800 solar panel equals a $100 battery - if it is working.I'd certainly agree that the panels sourced from AS are not cost effective. I got mine essentially free, and they do provide some useful charge. It takes very little to hold a 12 or even 16AH LFP in place. A simple tray with a strap over the top is
So, have you measured the outrush current caused by connecting the fully charged 12 AH battery in parallel with the partially discharged 20 AH battery (which I presume you still use)?Not sure what battery you are referring to. I don't have the 20 AH instrument battery under the knees, not installed. There is no way to parallel the batteries in my glider. Instruments stay on the 12 AH all day every day. If I ever have to switch
Tom
On Thursday, December 15, 2022 at 1:21:17 PM UTC-8, 2G wrote:convenient than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of a
On Thursday, December 15, 2022 at 8:45:35 AM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 11:17:26 PM UTC-8, 2G wrote:
On Wednesday, December 14, 2022 at 10:19:44 PM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much more--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
clouds (by actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to align andI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that under
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
all that is necessary.The connector is not the issue: it is the battery tie-downs that take the time. I decided that the $2,800 solar panel equals a $100 battery - if it is working.I'd certainly agree that the panels sourced from AS are not cost effective. I got mine essentially free, and they do provide some useful charge. It takes very little to hold a 12 or even 16AH LFP in place. A simple tray with a strap over the top is
instruments to the engine battery it is a rotary switch, break before make. In practice the only time I ever run the instruments off of the engine start battery is to do some quick chore like download logs with the instrument battery not installed. ButSo, have you measured the outrush current caused by connecting the fully charged 12 AH battery in parallel with the partially discharged 20 AH battery (which I presume you still use)?
TomNot sure what battery you are referring to. I don't have the 20 AH instrument battery under the knees, not installed. There is no way to parallel the batteries in my glider. Instruments stay on the 12 AH all day every day. If I ever have to switch
On Thursday, December 15, 2022 at 4:17:47 PM UTC-8, jfitch wrote:more convenient than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of
On Thursday, December 15, 2022 at 1:21:17 PM UTC-8, 2G wrote:
On Thursday, December 15, 2022 at 8:45:35 AM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 11:17:26 PM UTC-8, 2G wrote:
On Wednesday, December 14, 2022 at 10:19:44 PM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
clouds (by actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to align andI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that under
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
is all that is necessary.The connector is not the issue: it is the battery tie-downs that take the time. I decided that the $2,800 solar panel equals a $100 battery - if it is working.I'd certainly agree that the panels sourced from AS are not cost effective. I got mine essentially free, and they do provide some useful charge. It takes very little to hold a 12 or even 16AH LFP in place. A simple tray with a strap over the top
instruments to the engine battery it is a rotary switch, break before make. In practice the only time I ever run the instruments off of the engine start battery is to do some quick chore like download logs with the instrument battery not installed. ButSo, have you measured the outrush current caused by connecting the fully charged 12 AH battery in parallel with the partially discharged 20 AH battery (which I presume you still use)?
TomNot sure what battery you are referring to. I don't have the 20 AH instrument battery under the knees, not installed. There is no way to parallel the batteries in my glider. Instruments stay on the 12 AH all day every day. If I ever have to switch
The current could be quite high, as I found with my transfer capacitor, but quite brief, as it was with the capacitor. Why didn't you use the avionics battery under the seat pan, just so you could remove the battery easily for charging? 12 AH, BTW,wouldn't be enough for me for a single decent flight.
TomHow did you test the current spike?
On Thursday, December 15, 2022 at 5:57:27 PM UTC-8, 2G wrote:more convenient than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of
On Thursday, December 15, 2022 at 4:17:47 PM UTC-8, jfitch wrote:
On Thursday, December 15, 2022 at 1:21:17 PM UTC-8, 2G wrote:
On Thursday, December 15, 2022 at 8:45:35 AM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 11:17:26 PM UTC-8, 2G wrote:
On Wednesday, December 14, 2022 at 10:19:44 PM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
clouds (by actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to align andI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that under
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
top is all that is necessary.The connector is not the issue: it is the battery tie-downs that take the time. I decided that the $2,800 solar panel equals a $100 battery - if it is working.I'd certainly agree that the panels sourced from AS are not cost effective. I got mine essentially free, and they do provide some useful charge. It takes very little to hold a 12 or even 16AH LFP in place. A simple tray with a strap over the
instruments to the engine battery it is a rotary switch, break before make. In practice the only time I ever run the instruments off of the engine start battery is to do some quick chore like download logs with the instrument battery not installed. ButSo, have you measured the outrush current caused by connecting the fully charged 12 AH battery in parallel with the partially discharged 20 AH battery (which I presume you still use)?
TomNot sure what battery you are referring to. I don't have the 20 AH instrument battery under the knees, not installed. There is no way to parallel the batteries in my glider. Instruments stay on the 12 AH all day every day. If I ever have to switch
wouldn't be enough for me for a single decent flight.The current could be quite high, as I found with my transfer capacitor, but quite brief, as it was with the capacitor. Why didn't you use the avionics battery under the seat pan, just so you could remove the battery easily for charging? 12 AH, BTW,
usually around half discharged after about a 6 - 7 hours flight. That is with the solar panels. But for 17 years I flew without the solar panels, and even with an AGM battery never ran out of power from the 12 AH. That is with a pretty full panel: COM,TomHow did you test the current spike?
When I bought my glider it did not have the avionics battery under the seat pan. It had a 12 AH battery on the shelf just as it has now. I've never missed the missing battery, and never missed having to complain about charging it. The 12 AH battery is
Remember some of us need the weight of a lead acid battery to keep us in proper cg...
by having 32 AH total onboard, enough for at least two long flights w/o recharging.I used a shunt resistor and a scope.
As I have already posted, my total drain is 2 A, so a 12 AH battery wouldn't last 6 hr IF it were fully charged. One must figure that about 1 hr of that is on the ground, so that would last me less than 5 hr flight time. I over-engineer the situation
load) I know the battery is NOT fully charged.
Since you really can't determine charge state from a lithium battery's voltage, I measure the amount of AHr delivered to the battery to confirm that it is fully charged. However, if I turn everything on and the voltage is less than 12.9 V (with a 2 A
Tom
On Thursday, December 15, 2022 at 10:45:16 PM UTC-8, jfitch wrote:more convenient than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of
On Thursday, December 15, 2022 at 5:57:27 PM UTC-8, 2G wrote:
On Thursday, December 15, 2022 at 4:17:47 PM UTC-8, jfitch wrote:
On Thursday, December 15, 2022 at 1:21:17 PM UTC-8, 2G wrote:
On Thursday, December 15, 2022 at 8:45:35 AM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 11:17:26 PM UTC-8, 2G wrote:
On Wednesday, December 14, 2022 at 10:19:44 PM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
under clouds (by actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to alignI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
top is all that is necessary.The connector is not the issue: it is the battery tie-downs that take the time. I decided that the $2,800 solar panel equals a $100 battery - if it is working.I'd certainly agree that the panels sourced from AS are not cost effective. I got mine essentially free, and they do provide some useful charge. It takes very little to hold a 12 or even 16AH LFP in place. A simple tray with a strap over the
switch instruments to the engine battery it is a rotary switch, break before make. In practice the only time I ever run the instruments off of the engine start battery is to do some quick chore like download logs with the instrument battery not installed.So, have you measured the outrush current caused by connecting the fully charged 12 AH battery in parallel with the partially discharged 20 AH battery (which I presume you still use)?
TomNot sure what battery you are referring to. I don't have the 20 AH instrument battery under the knees, not installed. There is no way to parallel the batteries in my glider. Instruments stay on the 12 AH all day every day. If I ever have to
wouldn't be enough for me for a single decent flight.The current could be quite high, as I found with my transfer capacitor, but quite brief, as it was with the capacitor. Why didn't you use the avionics battery under the seat pan, just so you could remove the battery easily for charging? 12 AH, BTW,
is usually around half discharged after about a 6 - 7 hours flight. That is with the solar panels. But for 17 years I flew without the solar panels, and even with an AGM battery never ran out of power from the 12 AH. That is with a pretty full panel: COM,TomHow did you test the current spike?
When I bought my glider it did not have the avionics battery under the seat pan. It had a 12 AH battery on the shelf just as it has now. I've never missed the missing battery, and never missed having to complain about charging it. The 12 AH battery
I used a shunt resistor and a scope.by having 32 AH total onboard, enough for at least two long flights w/o recharging.
As I have already posted, my total drain is 2 A, so a 12 AH battery wouldn't last 6 hr IF it were fully charged. One must figure that about 1 hr of that is on the ground, so that would last me less than 5 hr flight time. I over-engineer the situation
Since you really can't determine charge state from a lithium battery's voltage, I measure the amount of AHr delivered to the battery to confirm that it is fully charged. However, if I turn everything on and the voltage is less than 12.9 V (with a 2 Aload) I know the battery is NOT fully charged.
Tom
A 12-16AH Life battery added to the baggage shelf to power the avionics (as Jon does)situation by having 32 AH total onboard, enough for at least two long flights w/o recharging.
would allow you to disconnect the SLA in front, but leave it place to maintain balance.
The lead disk peg in my glider can hold 3 more disks, so I could add a disk, then remove
the disconnected battery to reduce the glider empty weight by about 10 pounds, while
maintaining the W&B. What a deal: reduce weight and complexity at the same time!
Eric
On 12/16/2022 8:38 AM, william feiges wrote:
Remember some of us need the weight of a lead acid battery to keep us in proper cg...
I used a shunt resistor and a scope.
As I have already posted, my total drain is 2 A, so a 12 AH battery wouldn't last 6 hr IF it were fully charged. One must figure that about 1 hr of that is on the ground, so that would last me less than 5 hr flight time. I over-engineer the
A load) I know the battery is NOT fully charged.
Since you really can't determine charge state from a lithium battery's voltage, I measure the amount of AHr delivered to the battery to confirm that it is fully charged. However, if I turn everything on and the voltage is less than 12.9 V (with a 2
--
Tom
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
On Thursday, December 15, 2022 at 10:45:16 PM UTC-8, jfitch wrote:more convenient than the avionics battery under the seat. The OP said he didn't want a third system - but in my glider it is not a third system. I have no avionics battery under the seat, so, same number of systems, just more accessible. In the event of
On Thursday, December 15, 2022 at 5:57:27 PM UTC-8, 2G wrote:
On Thursday, December 15, 2022 at 4:17:47 PM UTC-8, jfitch wrote:
On Thursday, December 15, 2022 at 1:21:17 PM UTC-8, 2G wrote:
On Thursday, December 15, 2022 at 8:45:35 AM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 11:17:26 PM UTC-8, 2G wrote:
On Wednesday, December 14, 2022 at 10:19:44 PM UTC-8, jfitch wrote:
On Wednesday, December 14, 2022 at 12:00:44 PM UTC-8, Eric Greenwell wrote:
On 12/14/2022 8:29 AM, jfitch wrote:
On Monday, December 12, 2022 at 12:47:16 PM UTC-8, Eric Greenwell wrote:...
Eric, not "every Schleicher self launcher". I have a 12AH LFP on the baggage shelf, removing it is a 5 second exercise. It will power the panel as long as any day lasts and is easily removed for recharging where every you'd like. Much--RR, thanks for getting me to re-think the safari charging situation. Was thinking I
would need to plug the donor into a charger right after disconnecting from the glider in
the morning (solar panel mounted to the trailer). Depending on the field, it may not be
easy to find/beg/borrow an AC outlet near the tarmac. But with something like a 100Ah
LFP donor, I could get 4-5 glider charges out of it before taking it off-field for
recharging overnight before a rest day.
thx, JJ
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications
under clouds (by actual measurement). After a long flight, for me about 6.5 hours, I'm down typically 5 or 6 AH. It does actually take 5 seconds or a bit less to remove the battery, without rushing. Maybe as much as 10 seconds to install, I have to alignI didn't realize you were using the 12Ah battery instead of the OEM battery - thought itMy panel draws about 1.5A as well. With the LFP you can use most of it, so it would run low at around 7 hours (I have tested that). But I have the solar panels, these contribute about half of that draw in the sun and a quarter of that
was "in addition to". I do have the OEM installed wiring, so I could use a battery like
you do. It'd have to bigger, say 16AH, because 12AH would be marginal with my 1.5 amp
panel draw.
--
Eric Greenwell - USA
- "A Guide to Self-launching Sailplane Operation" https://sites.google.com/site/motorgliders/publications
top is all that is necessary.The connector is not the issue: it is the battery tie-downs that take the time. I decided that the $2,800 solar panel equals a $100 battery - if it is working.I'd certainly agree that the panels sourced from AS are not cost effective. I got mine essentially free, and they do provide some useful charge. It takes very little to hold a 12 or even 16AH LFP in place. A simple tray with a strap over the
switch instruments to the engine battery it is a rotary switch, break before make. In practice the only time I ever run the instruments off of the engine start battery is to do some quick chore like download logs with the instrument battery not installed.So, have you measured the outrush current caused by connecting the fully charged 12 AH battery in parallel with the partially discharged 20 AH battery (which I presume you still use)?
TomNot sure what battery you are referring to. I don't have the 20 AH instrument battery under the knees, not installed. There is no way to parallel the batteries in my glider. Instruments stay on the 12 AH all day every day. If I ever have to
wouldn't be enough for me for a single decent flight.The current could be quite high, as I found with my transfer capacitor, but quite brief, as it was with the capacitor. Why didn't you use the avionics battery under the seat pan, just so you could remove the battery easily for charging? 12 AH, BTW,
is usually around half discharged after about a 6 - 7 hours flight. That is with the solar panels. But for 17 years I flew without the solar panels, and even with an AGM battery never ran out of power from the 12 AH. That is with a pretty full panel: COM,TomHow did you test the current spike?
When I bought my glider it did not have the avionics battery under the seat pan. It had a 12 AH battery on the shelf just as it has now. I've never missed the missing battery, and never missed having to complain about charging it. The 12 AH battery
I used a shunt resistor and a scope.by having 32 AH total onboard, enough for at least two long flights w/o recharging.
As I have already posted, my total drain is 2 A, so a 12 AH battery wouldn't last 6 hr IF it were fully charged. One must figure that about 1 hr of that is on the ground, so that would last me less than 5 hr flight time. I over-engineer the situation
Since you really can't determine charge state from a lithium battery's voltage, I measure the amount of AHr delivered to the battery to confirm that it is fully charged. However, if I turn everything on and the voltage is less than 12.9 V (with a 2 Aload) I know the battery is NOT fully charged.
TomI measured the current spike shorting two batteries together. I used a CTS 20 AH LFP fully charged, and a Stark Power 12 AH LFP close to fully discharged. This would be the situation in my glider if there were a way to parallel the start and avionics
I measured the current spike shorting two batteries together. I used a CTS 20 AH LFP fully charged, and a Stark Power 12 AH LFP close to fully discharged. This would be the situation in my glider if there were a way to parallel the start and avionicsbattery. To measure, I used a Fluke 200 Gs scope with a Fluke hall effect current probe, with 100 KHz bandwidth. Unfortunately we are living in the 19th century here and I can't post the pictures. The result was a current spike of 8 A decaying to 6 A
On Friday, December 16, 2022 at 6:24:24 PM UTC-7, jfitch wrote:battery. To measure, I used a Fluke 200 Gs scope with a Fluke hall effect current probe, with 100 KHz bandwidth. Unfortunately we are living in the 19th century here and I can't post the pictures. The result was a current spike of 8 A decaying to 6 A
I measured the current spike shorting two batteries together. I used a CTS 20 AH LFP fully charged, and a Stark Power 12 AH LFP close to fully discharged. This would be the situation in my glider if there were a way to parallel the start and avionics
Nice! thanks Jon, I really appreciate seeing data from a definitive experiment. Interesting how limited the spike was and how quickly it decayed. (I've always had problems trying to picture the simple RCL model attributes of a battery)
JJ
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