corn18
Village Idiot
- Joined
- Sep 9, 2021
- Messages
- 814
Finally remembered to bring the thermal imager with me to the 5er. Powered everything up and was pulling 300A. All the wires and connectors up to the cutoff switch were cool as a cucumber. The shunt and 400A type T fuse showed a little heat but nothing concerning. First hot spot was at the disconnect switch, which is weird. The actual connections on the switch were getting warm (not hot). They are connected with 1/4" tinned copper bus bar so not sure why they are getting hot. Will have to investigate.
The 4/0 wires for the inverter were getting hot as usual. Will double them up soon. The huge surprise was the BattleBorn surge current limiter. That thing was so hot that it nearly burned my fingers when I touched it. It has always been tucked away and not reachable so I never knew how hot it got. Putting the imager on it, there were 150+ deg F hot spots where the FETS touch the giant aluminum heat sync and the whole thing was HOT to the touch. That thing must be burning up hundreds of watts to heat. Even at half power, it was warm and wasting my precious Ah. Very irritating.
Not sure what I'm gonna do about it. I did do an experiment to see if having 4xSOK batteries requires the surge limiter. Interestingly, my two new batteries did not go into protect when I powered up the system. But the two older batteries did. So I ordered two new BMS's from SOK to see if that solves the problem. I definitely will be getting rid of the BB surge current limiter. Might have to reinstall my precharge circuit.
Would really like to know what that surge current limiter is doing after the initial startup. Maybe it isn't smart enough to remove itself from the current path after the initial surge to the inverter. Then it just becomes a furnace.
The 4/0 wires for the inverter were getting hot as usual. Will double them up soon. The huge surprise was the BattleBorn surge current limiter. That thing was so hot that it nearly burned my fingers when I touched it. It has always been tucked away and not reachable so I never knew how hot it got. Putting the imager on it, there were 150+ deg F hot spots where the FETS touch the giant aluminum heat sync and the whole thing was HOT to the touch. That thing must be burning up hundreds of watts to heat. Even at half power, it was warm and wasting my precious Ah. Very irritating.
Not sure what I'm gonna do about it. I did do an experiment to see if having 4xSOK batteries requires the surge limiter. Interestingly, my two new batteries did not go into protect when I powered up the system. But the two older batteries did. So I ordered two new BMS's from SOK to see if that solves the problem. I definitely will be getting rid of the BB surge current limiter. Might have to reinstall my precharge circuit.
Would really like to know what that surge current limiter is doing after the initial startup. Maybe it isn't smart enough to remove itself from the current path after the initial surge to the inverter. Then it just becomes a furnace.
