Seplos BMS "Output Short Circuit Protection"

[jsolar]

At one point, the warning 'Short circuit protection' appeared. It disappeared for a while and then reappeared. After that I turned off the protection.

 

[testtenor]

At one point, the warning 'Short circuit protection' appeared. It disappeared for a while and then reappeared. After that I turned off the protection.

Mine is really random. Sometimes it comes up, sometimes it doesn't. It's really odd. Seplos thought it was a loose wire, but I checked and torqued them all. I'm fairly sure something is up with the BMS. Hopefully they can send me a new one (with Bluetooth)

 

[Roswell Bob]

There's probably a comparator doing the short circuit protection, would be trivial to have the micro hold its signal low, or use an internal DAC to generate a bunch of different thresholds for different revisions of the board.

Yes, I understand that it is entirely possible to design a BMS that could defeat the hardware overcurrent protection. My point is that it is not a good idea to give a microprocessor based circuit the ability to turn off hardware over current. Over the years power engineers have been reluctant to have anything software/microprocessor orientated in the path of device protection. Micro comes up stupid and boom.

 

[testtenor]

As an update Seplos are sending a new BMS to me. Should be about a week to arrive. That SHOULD fix the issue (hopefully)

 

[edcoopered]

I think in some cases where people are getting this fault out of the box with Seplos there is something wrong with the BMS and disabling this protection just causes that fault to become very apparent when the BMS goes boom! That's why if you're getting this fault on day one, return the BMS, if you're getting it once a week/month/year, maybe consider disabling the protection - but make sure you've got adequate fuses in place.

 

[testtenor]

Everyone my new Seplos BMS arrived and its installed. Its the new V16

 

[Starman]

I had a similar problem. I turned off shortcut protection in the Solar monitor app and then bms exploded.
One FET burned out.. I replaced the FET and now it works fine. I would not recommend repeating my procedure because the PCB on the BMS could have burned. Maybe, you can try to replace the MOSFET before.

View attachment 121397

Hane you got a link to the MOSFETs you replaced them with as I need to get a couple ??