Been working on a project using a Tesla model 3 battery pack connected to a solar inverter. Its been running for a few weeks but hit an issue. The contactors are no longer closing. Opened the penthouse to find a suspicious smell. Opened the PCS to look for damage and spotted what's in the photo and the smell coming from near the DC-DC pins corner of the board.
1092002-00f stamped on the casing. I don't consider myself as having the skills for a repair of the quality I would be happy with. I wondered if anyone has seen this before? or has any insights?
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BMW E91 2006
ZombieVerter
GS450h
Outlander Charger DC/DC
Renault Kangoo 36kWh battery
FOCCCI CCS
Sorry to see that happen, I'm not the best repair guy out there but would be saying it's probably a bit past it now, quite a few burnt bits there, multi layer board and it probably relied on it all being nice as a heat sink also?
Any idea what actually caused it to fail?
What sort of 12V battery was connected? As the DCDC is susceptible to heavy voltage swings if not providing enough output/stabilisation with a battery.
Also the failure looks like cooking the pcb, possible heatsoak issue from lack of cooling.
Failure mode looks to be blown mosfet. More information is required on your setup.
Connected to a lead acid battery. Generally I would disconnected the PCS once the contactors had clicked in because of not having a circuit set up to handle the slightly higher voltage the PCS wanted to output. I noticed when the lead acid battery was connected to the PCS after contact to closing it would make a wine noise which would coincide with current flowing. I saw 50 amps being attempted to push into the battery.
Over testing I had the PCS connected and disconnected many times to cycle and test new code so on. Added to disconnecting the lead acid for long periods of time i wonder if the damage is down to my failings to provide what the PCS is happy with.
I wonder if others have seen similar and if we could find out what caused it.
tom91 wrote: ↑Mon Oct 21, 2024 4:52 pm
What sort of 12V battery was connected? As the DCDC is susceptible to heavy voltage swings if not providing enough output/stabilisation with a battery.
Also the failure looks like cooking the pcb, possible heatsoak issue from lack of cooling.
Failure mode looks to be blown mosfet. More information is required on your setup.
The board was not cooled but given that its out of the car and not using the charger side i doubt its overheating. The outer casing always been cool.
The set up has been following the GitHub battery emulator project.
