Home› BSS User Forum › BSS Archive Threads› Discussion› Soundweb Original

9088 Power supply problem

colbeecolbee Posts: 2
in Soundweb Original
Hi,

I had a 9088 with a popped PSU, PWM IC was dead, several resistors, one diode was shorted IGBT shorted.

replaced all of this, thorougly metered but cannot get supply to PWM ic correct at the moment and IGBT continues to pop. Presumably supply comes from bridge and is dropped to a suitable level via a reistor. Got abotu 180 DC on one side from the bridge, drops to 90VDC to supply the PWM ic which is far too high from what I can tell (my comparison unit stays steady at 25V DC)

I cant see how this supply to the PWM ic is regulated other than from the resistor.

Any advice here? The forum seems quiet.

Comments

  • GeorgeMGeorgeM Posts: 12
    If your PSU continues to pop after you have replaced a number of components, the answer is simple, you didn't find all the failed components.
    1 bad part left behind will cause the supply to pop again until you have found everything thats dead and replaced everything at the same time, otherwise its groundhog day.

    Parts that should be replaced by default are:

    Opt3 CNW11-AV1
    Opt4 CNW11-AV1
    IC15 UCC3842A
    R156 22R
    R159 1K
    R196 1R 1 Watt
    R197 1R 1 Watt
    D33 BYD73G
    TR13 P7NB60FP
    C60 47/50V
    C49 100/400V

    C60 should be a low esr 63V device.
    George.
This discussion has been closed.