Even the most Careful of us can be Stupid!!


Renewable energy user - North Carolina
Dec 19, 2021
Setting up a New Battery.

Setup all the busbars. Cleaned everything. Tighten them to specs.
Put the BMS on. Measured all the voltages.
All the while the wife and kid are arguing about something or other and I’m trying to referee.
I Attach the the power supply to charge it and go to figure out what the problem is.

Come back and find the first 4 cells at 3.7 volts.

Unplug the charger. Trying to figure out how?

Turns out I install the negative of the charger to the battery instead of the BMS.

No matter how careful you are, you can get distracted and make a mistake.

Be careful out there.
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Photon Vampire
May 1, 2021
It's not Stupidity, it's just distraction and it has happened to all of us.
I had to really yell at my wife and kids one day for that exact same reason. One of them called to me while I was probing a PCB and the probe slipped off an IC pin and shorted the two pins next to each other and killed a rather expensive device. I told them if I lose my concentration when working on stuff I could be seriously hurt.
Evidently they got the message because after that they really avoid disturbing me when I am working on something, unless it is a real emergency.