Sabvoton controller phase shorted with Battery positive

Roguenite

100 µW
Joined
Jun 26, 2020
Messages
7
Hello everyone,

I was hooking up my new Sabvoton controller (SVMC96120) to my 26s 5p battery pack to look at the controller settings on the laptop. The controller was fresh out of the box.
I first connected the battery negative to controller negative and then lost focus and connected BATTERY POSITIVE TO GREEN PHASE OF CONTROLLER.

The ANT BMS quickly took over and cut off but only after shorting just over 20A through the green color phase. The controller permanently has continuance between ground and positive now. Can't even connect the battery in the correct terminals anymore. (I tried 😊)

I checked the FETS and all 10 FETS of the green phase has 0 resistance between the pins. So I took out all 10 of them and ordered new FETS. They will arrive in a couple of weeks.

The reason I am posting here is because when I check the resistance of the tiny SMD resistors next to the FETS, the resistors of the burnt FETS don't match the healthy ones in value. There is 1 resistor for each FET. The 10 resistors in blue phase and 10 resistors in yellow phase all reads 2.00 on multimeter at 20k scale.

But the 5 resistors of positive side of burnt phase reads 2.5 and the 5 resistors of negative side of burnt phase reads 1.10 on 20k scale.

UPDATE: I didn't read the resistor values until after I removed all of the burnt FETS. Can the values be different because the FETS are missing? But I am reading the resistors from their body end to end. So, presence of any outside components can't change the value of the internal resistance of these SMD's right? I hate resistors because I dont understand them

Would this still cause a problem after i solder in the new FETS?

2021-8-29 12-36-1.jpg

The SMD resistors are 1002 in dimensions (1mmx2mm) i think. This size is way beyond my soldering skills. And there are 10 of them. I paid £350 for this controller and didn't even get to plug the motor even once. This is a Stealth bomber in progress.

So will the resistance difference on a 20k scale be an issue? I am not very good with resistance math and logics.

Thanks so much for any help.

😭
 
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