On 06/02/2021 10:45, Cursitor Doom wrote:
Hi all,
I came across a novel situation yesterday. I yanked this
in-need-of-a-charge battery out of a 3 litre diesel BMW to top it up
on my bench charger. It's one of those with the status window:
'replace', 'charge' or 'OK' and that window was black/blank,
indicating a charge was in order. Things seemed to be proceeding
normally according to the charger current meter (started off at ~5A
and gradually came down over a few hours) but when I checked the
terminal voltage (with the charger attached and on) I got 15V
Once fully charged a lead acid is effectively o/c and terminal voltage >dependent on the charger and the voltage across the plates from
electrolysing the electrolyte. Since you're using electrolyte it's not a
good position to be in.
Most old trickle chargers could easily get to 15V and nothing to really
worry about.
It does indicate a full charge, or as full as it's going to get.
which
seems an awful lot for a trickle charge. The status window remained
unchanged. I'm not happy about the 15V bit. It came down to a more
normal 12.4V after being turned off for a while, though.
Does that 15V indicate some issue with the battery?
Most indicators rely on the electrolyte on a window, and the reflection >dependent on level only.
I guess it might be possible for the reflection be dependent on the >electrolyte refractive index which no doubt will be sensitive to SG.
Perhaps someone will be along to confirm or say is nonsense?
How confident are you the electrolyte is above the plates?
Hi all,
I came across a novel situation yesterday. I yanked this
in-need-of-a-charge battery out of a 3 litre diesel BMW to top it up
on my bench charger. It's one of those with the status window:
'replace', 'charge' or 'OK' and that window was black/blank,
indicating a charge was in order. Things seemed to be proceeding
normally according to the charger current meter (started off at ~5A
and gradually came down over a few hours) but when I checked the
terminal voltage (with the charger attached and on) I got 15V
which
seems an awful lot for a trickle charge. The status window remained unchanged. I'm not happy about the 15V bit. It came down to a more
normal 12.4V after being turned off for a while, though.
Does that 15V indicate some issue with the battery?
Hi all,
I came across a novel situation yesterday. I yanked this
in-need-of-a-charge battery out of a 3 litre diesel BMW to top it up
on my bench charger. It's one of those with the status window:
'replace', 'charge' or 'OK' and that window was black/blank,
indicating a charge was in order. Things seemed to be proceeding
normally according to the charger current meter (started off at ~5A
and gradually came down over a few hours) but when I checked the
terminal voltage (with the charger attached and on) I got 15V which
seems an awful lot for a trickle charge. The status window remained >unchanged. I'm not happy about the 15V bit. It came down to a more
normal 12.4V after being turned off for a while, though.
Does that 15V indicate some issue with the battery?
With some of the trickle charger / maintenance chargers its not
unusual for them to output 15 or 16 volts part way through their
cycle, its part of the conditioning cycle it applies to the flat
battery
On Sat, 06 Feb 2021 20:54:14 +0000, steve robinson <steve@colevalleyinteriors.co.uk> wrote:
With some of the trickle charger / maintenance chargers its not
unusual for them to output 15 or 16 volts part way through their
cycle, its part of the conditioning cycle it applies to the flat
battery
I should perhaps have mentioned this is one of the old-style car
battery chargers with no 'brain' at all. Manual selection of 12 or 24V
and high and low charge rates. That's all there is to it.
On 06/02/2021 21:17, Cursitor Doom wrote:
On Sat, 06 Feb 2021 20:54:14 +0000, steve robinsonStill got a DVM though by the sound of it. My default machine has a
<steve@colevalleyinteriors.co.uk> wrote:
With some of the trickle charger / maintenance chargers its not
unusual for them to output 15 or 16 volts part way through their
cycle, its part of the conditioning cycle it applies to the flat
battery
I should perhaps have mentioned this is one of the old-style car
battery chargers with no 'brain' at all. Manual selection of 12 or 24V
and high and low charge rates. That's all there is to it.
proper moving iron ammeter and no voltage display at all.
On Sat, 6 Feb 2021 12:47:08 +0000, Fredxx <fredxx@nospam.co.uk> wrote:
Most indicators rely on the electrolyte on a window, and the reflection
dependent on level only.
I guess it might be possible for the reflection be dependent on the
electrolyte refractive index which no doubt will be sensitive to SG.
Perhaps someone will be along to confirm or say is nonsense?
You're probably right. I'd never thought about it too deeply and just
assumed they use some sort of micro-power LED 'traffic light' system
deep in a tube with lenses to make the dim glow more visible on the
exterior.
I'll check out the electrolyte level. It's supposed to be
maintenance-free but...... best check in case....
Charge indicator built into battery is just a battery hydrometer. A
float that when the battery is charged will float higher and becomes
visible in the window.
On 06/02/2021 18:47, Cursitor Doom wrote:
On Sat, 6 Feb 2021 12:47:08 +0000, Fredxx <fredxx@nospam.co.uk> wrote:
Most indicators rely on the electrolyte on a window, and the reflection
dependent on level only.
I guess it might be possible for the reflection be dependent on the
electrolyte refractive index which no doubt will be sensitive to SG.
Perhaps someone will be along to confirm or say is nonsense?
You're probably right. I'd never thought about it too deeply and just
assumed they use some sort of micro-power LED 'traffic light' system
deep in a tube with lenses to make the dim glow more visible on the
exterior.
I'll check out the electrolyte level. It's supposed to be
maintenance-free but...... best check in case....
Charge indicator built into battery is just a battery hydrometer. A
float that when the battery is charged will float higher and becomes
visible in the window.
Some have 2 concentric floats. A ball that shows charge and 2nd one that >shows level of electrolyte.
On Mon, 8 Feb 2021 12:06:13 +0000, Peter Hill <skyshac@yahoo.com>
wrote:
On 06/02/2021 18:47, Cursitor Doom wrote:
On Sat, 6 Feb 2021 12:47:08 +0000, Fredxx <fredxx@nospam.co.uk> wrote:
Most indicators rely on the electrolyte on a window, and the reflection >>>> dependent on level only.
I guess it might be possible for the reflection be dependent on the
electrolyte refractive index which no doubt will be sensitive to SG.
Perhaps someone will be along to confirm or say is nonsense?
You're probably right. I'd never thought about it too deeply and just
assumed they use some sort of micro-power LED 'traffic light' system
deep in a tube with lenses to make the dim glow more visible on the
exterior.
I'll check out the electrolyte level. It's supposed to be
maintenance-free but...... best check in case....
Charge indicator built into battery is just a battery hydrometer. A
float that when the battery is charged will float higher and becomes
visible in the window.
Some have 2 concentric floats. A ball that shows charge and 2nd one that
shows level of electrolyte.
Thanks. It's now become visible once more. Must have got stuck for
some reason deep down in its tube.
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