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miya avatar image
miya asked

Cerbo GX / Lynx Smart BSM - losing state of charge and consumed Amps

Hi All

I am a little confused by something my Cerbo and Lynx Smart BMS are doing.

Batteries charged to 100% - and showing the same in Lynx Smart BMS and GX Touch Screen. I pull about 50 amp of the batteries - the % SOC reduces correctly and consumed Amps on VRM show the same. All good so far !

I then use VictronConnect to switch the Lynx Smart BMS off - for a few hours, then switch it back on, a few hours later, but the old values when I switched off - are lost. The %SOC and Consumed Ah revert to what they were the previous time the BMS was switched on.

Any ideas what is happening here ?

Thanks

Tim





cerbo gxBMS
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2 Answers
Stefanie (Victron Energy Staff) avatar image
Stefanie (Victron Energy Staff) answered ·

@Miya

Where are these values reset, in VictronConnect, GX device or VRM? Screenshots?

I cannot confirm this. VictronConnect and the GX device show exactly the same values as before the system was switched off. But I've seen something like this before on VRM.

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miya avatar image miya commented ·

Hi Stefanie

The values reset in VRM, VictronConnect, in all places.

See screenshot of consumed Ah in VRM (and I see the same on Smart BMS when viewed on VictronConnect -

screenshot-2022-08-21-at-134823.png

I woke up - consumed Ah show at 48.6 - which I would expect as batteries fully charged night before. Switched OFF BMS via VictronConnect - for a while - when I switched back on - consumed Ah had jumped up to 31.7Ah. Left on for a while and tested again - and you see it jumped back to 31.7Ah again.

Kind regards

Tim

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screenshot-2022-08-21-at-134823.png (86.0 KiB)
Stefanie (Victron Energy Staff) avatar image Stefanie (Victron Energy Staff) ♦♦ miya commented ·
I haven't checked consumed Ah, only SoC because that's what you said in your initial post, but will do and then report back.
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miya avatar image miya Stefanie (Victron Energy Staff) ♦♦ commented ·

Sorry... the same appears on VRM and BMS for SOC

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Stefanie (Victron Energy Staff) avatar image Stefanie (Victron Energy Staff) ♦♦ miya commented ·

It's working for me as intended. Both values update to their values like they have been before switching off.

What are your Lynx Smart BMS settings? Please post a screenshot.

What firmware version is your Lynx Smart BMS running on?

And did you switch it into OFF or Standby mode?

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miya avatar image miya Stefanie (Victron Energy Staff) ♦♦ commented ·

Hi Stefanie

BMS settings....

screenshot-2022-08-21-at-172454.pngscreenshot-2022-08-21-at-172506.png

Firmware.... 1.05

screenshot-2022-08-21-at-173146.png

I switched it to OFF - using the VictronConnect App over Bluetooth - so the Cerbo was powered down too.

Thanks for looking at this for me Stefanie.

Kind regard

Tim

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screenshot-2022-08-21-at-172454.png (161.1 KiB)
screenshot-2022-08-21-at-172506.png (199.2 KiB)
screenshot-2022-08-21-at-173146.png (96.7 KiB)
Stefanie (Victron Energy Staff) avatar image Stefanie (Victron Energy Staff) ♦♦ miya commented ·

Thanks again!

I've now been able to reproduce this, albeit on a smaller scale (needed to put a larger load on to see the effect) and will pass this on to the developers.

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miya avatar image miya Stefanie (Victron Energy Staff) ♦♦ commented ·
Thanks Stefanie - much appreciated.
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Stefanie (Victron Energy Staff) avatar image Stefanie (Victron Energy Staff) ♦♦ miya commented ·

A temporary solution: If you use a physical remote on/off switch between pin 10 and 11, it works as it should and shows the values that existed before it was switched off.

I have tested this over night.

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miya avatar image miya Stefanie (Victron Energy Staff) ♦♦ commented ·

Thanks Stefanie - Thats great. As always - greatly appreciate your support / help.

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johanndo avatar image
johanndo answered ·

If you power down the system, it has no idea what happens between this and turning back on, it needs resynching, as it has a complete unmonitored blackout for a extended time. Don't power down your monitoring gear.

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