200ah smart battery BMS leads installed backwards at factory?

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vwhammer asked Feb 1, '22

200ah smart battery BMS leads installed backwards at factory?

So two 12v 200ah Victron Smart batteries were installed in a complete system with Lynx BMS and sent on its way.

I was contacted about a week later because they were getting a low voltage alarm and the system was not shutting down as it should.

I checked and rechecked the wiring and it all seemed fine.

I swapped batteries and it all seemed to work and I have not heard from them since.

Assuming there was an issue with the batteries I took a hard look at them.

They both recharged just fine but then I went to put them back in another system for testing and realized that the BMS leads on one of the batteries was swapped.

This is how they are supposed to look

[img]https://i.imgur.com/8c8rMdE.jpg[/img]

But one of them looks like this

[img]https://i.imgur.com/86Syqva.jpg[/img]

I don't know if they are switched internally or if they were just put in the wrong slots on the battery case during assembly.

I can't help but think that this is why the BMS never got the signal and thats why it did not shut down.

Anyone have any input on how the communication works between the BMS and the batteries and if this would wreck that?

Lithium Battery

2 |3000

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Answer 1 · 2022-02-01T18:21:56Z

Stefanie (Victron Energy Staff) answered · Feb 01, 2022 at 06:21 PM

Hi @vwhammer

This shouldn't happen under any circumstances, but apparently that's what happens then, unfortunately.
I can't say anything concrete about the communication. Basically the circuit board (called BTV) talks to the BMS by sending signals when temperature is high/low or cell voltage is high/low.
But I opened a SmartLithium. The circuit board clearly and unambiguously states which wire color has to be soldered to which point on the circuit board and on which side the plug and socket should come out.

If you look at the two black cables from the outside, the male connection comes out on the right side, the female on the left side.

I guess this qualifies for warranty.

VB22-AU004766

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

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