I have need for a 8-16 channel I2C in, relay out expansion board.
We're now using:
<https://www.ereshop.com/shop/free/I2C-RL8xxM_SHEET.pdf>
but the shipping is insane.
So I'm seeking an alternative supplier. I figure one approach is
to find a forum where Arduino users hang out, and ask there.
Any suggestions for board suppliers or forums?
PCF8574-I2C-Bidirectional-I-O-Expander-Relay-Control-SmartHome-Ardiuno-Raspberry
https://www.ebay.com/itm/282692860765 US $2.90
Used with:
/8-Eight-Channel-5V-Relay-Module-Board-with-Optocoupler-Power-Supply-PIC-ARM
https://www.ebay.com/itm/322834065204 US $6.39
gives you eight relays for $9.29 plus some wires between the modules.
Michael A Terrell <mike.terrell@earthlink.net> writes:
PCF8574-I2C-Bidirectional-I-O-Expander-Relay-Control-SmartHome-Ardiuno-Raspberry
https://www.ebay.com/itm/282692860765 US $2.90
Used with:
/8-Eight-Channel-5V-Relay-Module-Board-with-Optocoupler-Power-Supply-PIC-ARM
https://www.ebay.com/itm/322834065204 US $6.39
gives you eight relays for $9.29 plus some wires between the modules.
Seen many versions of that. Want an integrated board w/relays. Found
several but all thus far are international $hipping.
Michael A Terrell <mike.terrell@earthlink.net> writes:
PCF8574-I2C-Bidirectional-I-O-Expander-Relay-Control-SmartHome-Ardiuno-Raspberry
https://www.ebay.com/itm/282692860765 US $2.90
Used with:
/8-Eight-Channel-5V-Relay-Module-Board-with-Optocoupler-Power-Supply-PIC-ARM
https://www.ebay.com/itm/322834065204 US $6.39
gives you eight relays for $9.29 plus some wires between the modules.
Seen many versions of that. Want an integrated board w/relays. Found several but all thus far are international $hipping.
OK, make your own. A schematic of that board is online.
Michael A Terrell <mike.terrell@earthlink.net> writes:
OK, make your own. A schematic of that board is online.
Worst option. Avoiding manufacturing anything; just exponential time-sink. Would prefer the integrated board but may end up with split approach.
I don't follow what is so bad about international shipping? The typical >vendor of inexpensive boards is in Asia and ships for free. I found two on >eBay that sell 8 channel I2C relay boards with a different form factor for >$80 or $90 in the US. Where are you?
The split configuration would make it easier to repair, and the
control boards can be plugged end to end. You can eliminate the jumpers
on the headers with a drop of solder on the underside of the boards.
If a relay board or controller board fails, it will be much cheaper
to repair. You can buy ready made 40 conductor cables with single Dupont >contacts on Ebay to harness them together. I remove the single contact
shells and replace them with a single, with the proper number of
positions. That way, my projects look a lot neater than the typical wad
of individual wires.
Michael A Terrell <mike.terrell@earthlink.net> writes:
The split configuration would make it easier to repair, and the
control boards can be plugged end to end. You can eliminate the jumpers
on the headers with a drop of solder on the underside of the boards.
If a relay board or controller board fails, it will be much cheaper
to repair. You can buy ready made 40 conductor cables with single Dupont
contacts on Ebay to harness them together. I remove the single contact
shells and replace them with a single, with the proper number of
positions. That way, my projects look a lot neater than the typical wad
of individual wires.
40?
I need some 10 position one-row headers but will likely use
two-row 20's and ignore the other. I do plan to plug them end
to end but will need to hold them. Thinking a slotted /______\
piece of soft plastic that in turn is mounted to the DIN rail.
Michael A Terrell <mike.terrell@earthlink.net> writes:
I need some 10 position one-row headers but will likely use
two-row 20's and ignore the other. I do plan to plug them end
to end but will need to hold them. Thinking a slotted /______\
piece of soft plastic that in turn is mounted to the DIN rail.
Yes, ribbon cable. Peel off as many conductors as you need. The color
code repeats every ten conductors.
T1-3X-40pcs-20cm-Male-To-Male-Female-Dupont-Wire-Jumper-Cable-Arduino-Breadboard
https://www.ebay.com/itm/231708399395
I'd rather use an IDC connector that matches the headers; less
chance something gets loose/ is misconnected.
I need some 10 position one-row headers but will likely use
two-row 20's and ignore the other. I do plan to plug them end
to end but will need to hold them. Thinking a slotted /______\
piece of soft plastic that in turn is mounted to the DIN rail.
Yes, ribbon cable. Peel off as many conductors as you need. The color
code repeats every ten conductors.
T1-3X-40pcs-20cm-Male-To-Male-Female-Dupont-Wire-Jumper-Cable-Arduino-Breadboard
https://www.ebay.com/itm/231708399395
The IDC connector is a solid block and fixed size. The "Dupont" cables can >be used in any width or as individual wires. The connectors on the end >aren't tied on with string. They work great. You can get them in either >male or female on both ends and in any combination. Very flexible indeed.
rickman <gnuarm@gmail.com> writes:
The IDC connector is a solid block and fixed size. The "Dupont" cables can >> be used in any width or as individual wires. The connectors on the end
aren't tied on with string. They work great. You can get them in either
male or female on both ends and in any combination. Very flexible indeed.
Yes, I see. But they are fixed length. With ribbon+IDC, I can make the cables the correct length.
Michael A Terrell <mike.terrell@earthlink.net> writes:
I need some 10 position one-row headers but will likely use
two-row 20's and ignore the other. I do plan to plug them end
to end but will need to hold them. Thinking a slotted /______\
piece of soft plastic that in turn is mounted to the DIN rail.
Yes, ribbon cable. Peel off as many conductors as you need. The color
code repeats every ten conductors.
T1-3X-40pcs-20cm-Male-To-Male-Female-Dupont-Wire-Jumper-Cable-Arduino-Breadboard
https://www.ebay.com/itm/231708399395
I'd rather use an IDC connector that matches the headers; less
chance something gets loose/ is misconnected.
David Lesher wrote:
Michael A Terrell <mike.terrell@earthlink.net> writes:
I need some 10 position one-row headers but will likely use
two-row 20's and ignore the other. I do plan to plug them end
to end but will need to hold them. Thinking a slotted /______\
piece of soft plastic that in turn is mounted to the DIN rail.
Yes, ribbon cable. Peel off as many conductors as you need. The color
code repeats every ten conductors.
T1-3X-40pcs-20cm-Male-To-Male-Female-Dupont-Wire-Jumper-Cable-Arduino-Breadboard
https://www.ebay.com/itm/231708399395
I'd rather use an IDC connector that matches the headers; less
chance something gets loose/ is misconnected.
Really? Have you ever used the Dupont connectors? They are reliable, and inexpensive.
I've used thousands of them, along with IDC. Only a keyed header and a keyed IDC connector will prevent misconnecting a cable. The color coded wire that I mentioned makes it easy, since they follow the standard color code. Start with black for pin one. Consider it the stripe on typical ribbon cable.
Shouldn't black be pin zero?
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