Ps 2524E

I have a problem with the fet. board, 6 of the 'n' channel fets have blown up, however, I removed the unit complete with heat sync. slid out the board and replaced the 6 fets and their 100 ohm resistors, I also found that the mosfet driver TC1427CPA had blown, which I also replaced, 2 capacitors 1N J100 had melted so I replaced them with 3.3N J100, put the lot back together and it blew again!!!! Anybody, any ideas?

P.s. Could this have affected the control board in any way? At the moment when I put power to the unit, a red light comes on with yellow flashing but no buzzing noise.

Comments

  • boB
    boB Solar Expert Posts: 1,030 ✭✭✭✭
    Re: Ps 2524E

    I always re-power with a lower power supply rather than batteries. What kind of FETs did you use ? There are most likely better FETs out these days than they used originally.
    Are you sure the HCPL-3120 high side drivers were OK ? They rarely go but would be good to check anyway.

    Gate drive resistors good? Maybe those were the R's you did replace.

    While on the power supply, you might want to check drive waveforms of at least the low side FETs, or the center of the 1/2 bridges to make sure they are switching between ground and battery plus.

    If you suspect any problems from the control board, check the input to the FET drivers.

    Do the other 2 inverter sections appear to be working OK ?

    Maybe this attached picture can help to visualize the separate sections (small, medium and large transformers) and how the add up to make the final sinewave. The individual waveforms will change slightly while regulating due to battery voltage and load changes. I think that the PS had two smaller transformers in parallel to make up the one large transformer.

    boB