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miya avatar image
miya asked

Smart BMS / Smart Lithium / MultiPlus II - Strange Spike in Charge Profile

Hi All

This may be nothing to worry about - but I have a strange spike in the charge profile - as just after Absorption - when the V is dropping down to Float. See graph -

screenshot-2022-08-30-at-111110.png

The Amps jump us, only for a few minutes, to 11A, when they should be dropping to NIL, and the V on batteries increase to 13.35v for a short time.

There are no loads or charging sources attached. Nothing.

Anything to worry about why this happens ? It always happens on very charge.

Thoughts ?

Thanks

Tim

Multiplus-IIBMSsmart lithium
screenshot-2022-08-30-at-111110.png (153.8 KiB)
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Trevor Bird avatar image Trevor Bird commented ·
Hello @Miya .....an Interesting observation. You mention no charging sources?? Surely a charging source must be connected to have such a charge profile?? I wonder what the charger is?

Regards,

Trevor

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miya avatar image miya Trevor Bird commented ·
Hi Trevor

Well spotted... sorry... was typing this in a rush. It should have said "no other charging sources other than the MultiPlus II".

Thanks, Tim

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Stefanie (Victron Energy Staff) avatar image
Stefanie (Victron Energy Staff) answered ·

@Miya,

To me it looks like a load has been calling for power and the Multi is taking some time (it's really only seconds and looks more dramatic than it really is on the graph) to regulate the extra power (beyond what is needed for the charger). I've seen that on my system as well, but not on a regular basis e.g. on every full charge. Nothing to worry about.

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miya avatar image miya commented ·

Hi Stefanie

Yes - that would explain it to me too - if a load was on, switched off, the Amps would jump before the Multi could reduce Amps to compensate. The only load connected it the Cerbo & Touch (attached directly via AUX power to Lynx Smart BMS).

Very odd - this happens every charge cycle. With no loads attached.

I am probably worrying too much about the magic absorption value of 14.2v. If you say it's OK to go to 14.35v for a few minutes - I'll forget about this spike and stop worrying.

Thanks Stefanie.

Ta

Tim

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