| berty1 |
Hi,
I'm trying to repair Behringer PMP3000 mixer/amp. It has a fault in the PSU section.
The PSU PCB is SPS1000/02.
I really could do with a schematic. So if anyone knows the where I can get one I would be grateful.
The closest schematic I can find is a Yamaha EMX5000. This seems to be 'sort of' similar around the PSU section. Someone has copied someone !!!!!
The component damage was as follows:-
22R 10W mains input resistor blown apart.
IGBT's 1MBK50D-060S short circuit
Diode on the gate of one of the IGBT's short circuit
I have also replaced the IR2153 device.
When I apply power the relay, across the two 22R 10W resistors is not engaging. ( presumably cuz no 12V present to energize it ) so I have to turn off quickly. So fault is still there.
Is it OK to bring these types of PSU up using a variac ?. If so what voltage would you expect the PSU to start working at ?
I cant leave power on for long enough to try to fault find.
And I have no shematic to try to isolate sections.
So any help appreciated.
Thanks
Albert |
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| Eva |
Trace the 12V source :)
Is the IR2153 receiving the proper supply voltage while the relay doesn't? |
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| berty1 |
Thanks for the reply.
The IR2153 is supplied by a TOP221 as opposed to a linear regulator.
The problem is I can't apply power long enough to probe around to see what voltages there are.
I was wondering if I could lower the mains input voltage with a variac to a safe level that the PSU would still operate, but with out burning up the 22R resistors!!.
I assume the two 22R 10 watt resistor in series with the mains input are for slow switch on.
I've traced one side of the relay to the collector of an other transistor.
This implies that the relay is switched somehow !!
I really am snookered without a schematic.. |
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