question

dazey77 avatar image
dazey77 asked

BMV-712 Smart- Possible to activate relay on full battery?

Is it possible to get the relay to activate on a high SOC rather than a low one? I see there is an option to invert the relay and if I set a high range for the relay (e.g. 95-98%) then this achieves the relay output I want but the problem is that this kills the time-remaining estimates.

Is there some other way to get a signal that the battery is full?

If I invert the relay on 20-98% I don't think this achieves what I want as the set point is still 20%?

Thanks in advance

BMV Battery Monitor
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3 Answers
Mark avatar image
Mark answered ·

Unfortunately, as you pointed out - the lower SOC relay setting is linked to the time to go calc. So you cant use it to trigger a relay when fully charged (based on SOC) and provide a sensible time to go reading.

It's primarily setup as a low SOC relay - not high SOC.

Its not as ideal, but maybe consider tripping the relay on voltage instead?

Or just forget about your time to go calculation if the relay is more important.

It would be nice if the trigger for each was independent...

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dazey77 avatar image
dazey77 answered ·

Thanks for the response. Roughly what I figured then, had hoped I was missing something!

I guess I will wire it up and see which works best for me. There is the chance that the time to go is going to be useless anyway as my biggest loads are irregular (compressor fridge and heater).

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Mark avatar image
Mark answered ·

No worries.

The time to go also has an adjustable 'averaging period' that can help in some cases, but it will still only calculate based off the loads active/on during the averaging period - it's not psychic to know what might turn on later... :-)

Once the larger loads turn on the time will adjust accordingly (subject to averaging period), however the revised time would again be based on the assumption that the current loads remain active/on.


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