62.1 Voltage reading from my 12S3P battery?

I want to know exactly what’s wrong with my board and just replace components my self, but I’ve been going back and forth with Onsra and they asked me to check the voltage of the battery.

I connected my multimeter directly to main battery output 12 gauge wires/XT90 connector and got a reading of 62V. This doesn’t seem correct. It’s a 12S3P pack built with Samsung 30q’s (IIRC). So from looking at the specs, when the battery is fully charged it should be ~52V and if it was absolutely dead at the discharge cutoff it would be 30V.

Why would the multimeter be giving my this voltage reading? Do I have it setup correctly? You can see in the picture what the dial is set too, etc. Please reference the picture.

Let me just explain 1 more symptom. When the enclosure with everything is turned upside down the board can power on and spin the motors, but once I flip the enclosure back over on the board how it’s supposed to be it instantly shuts off.

Thanks!

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Oh wow! Not sure why that battery pack is not on fire right now. Sounds like you know this already, but full charge for a 12s lipo or li-ion pack should not exceed 4.2v per cell or 50.4v.

Gonna take a wild guess here and say somethings up with that voltmeter. Recommend you try measuring whatever else you have thats accessable, car batteries or whatever. Or if you have another meter, try that. I’ve got an old Sperry multimeter here thats awfully dodgy. Thinking that may be the issue.

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Cant quite make out the symbols on your meter. Are you sure you’re not on the AC side?

Yeah it’s saying this Molicel P26A is 5.2 volts, but that’s not right. I used this cell the other day and it was fine. Alright, I’m off to buy a new multimeter.

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Hold the phone. It looks like you’re in the AC range on that meter. Recommend you find an instruction manual before spending money on another meter.

I read the manual, etc. It’s definitely on the voltage setting. All good I just bought a new Klein Tools and voltage checks out now.

At least was able to identify 1 fault. Too bad it wasnt with the board itself. :joy:

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Also, thanks for the input guys. Once my VESC arrives I’ll have some more annoying questions for y’all. :grin:

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I’m kinda late here, but yes, your multimeter isn’t reading the battery right. Glad you solved that.

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Change battery in previous voltmeter. I can see “low battery” icon on bottom left corner of display. Those cheap meters tend to go bonkers with low battery. Meter itself might be ok and read well - check it.

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I second @FullMetal_Machinist

When the battery is low, a lot of times they do this.

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