Behringer europower pmh1000 blown psu

[laserlight]

Hi all. I have a question about this mixer. The psu has blown and I was wondering if anyone know likely components that go. I know its a longshot but am sure their must be some engineers out there that fix them. I am an electronics engineer myself so am pretty competent when it comes to these things, but frankly, switchmodes are a bastard even with a schem so without one I def need help! anyway, the 2 cool mos transistors (17n80c3) which im assuming are the primary side chopping transistors have blown. This has also taken out R58,R59,R67,R68 surface mount. cant quite make out value but think is .47 or 47 ohms and are connected from -o/p of bridge rect to the top221p mosfet pwm controller. Also gone are R34,R43 and C7. These are just the smd's that have obviously blown by looking at them. I havent got down to checking other things with ohmeter/diode checker yet. Am I wasting my time or does anyone know if this is a classic chain of components that goes and what else should be changed?
would really appreciate any help. thanks

[Enzo]

The four resistors are 0.047 ohms, yes 47 milliohms. Those and the switchers would be a common enough failure.

Those last few parts are scattered around the circuit. I'd say that is a darned odd collection of burnt parts.

before going too far, check the powr amp modules for shorted output transistors. Usually the SMPS dies for a reason.

And Behringer keeps close tabs on their schematics, but there are some out there if you search google well enough. I think we have discussed this here too and left some links. Find the PMH1000 schematic set. Also search PMX1000, as many people see the stylized H and think it is an X.

[laserlight]

Thanks for that.got schem now so should have half a chance. will check output stage on amp. .047R res should be interesting to source! guess I could use .1's in parallel if needed. havent even looked at the 2 pmh3000's I have with blown psu's yet! beginning to wish I hadnt offered to fix them. never mind, I like a challenge.

[Enzo]

0.047 ohm, I just bought some at Mouser. Fractional ohm resistors like that are more common than you might think. The 17N whatevers are out of stock. I stock the TOP221 and stuff.

If you get the SMPS running on the bench, those +/-V rails can stay charged a long time. Check with a meter. Always discharge them before reconnecting the powr amps.

[silviutu]

Hi! Please!! I need the diagram pmh1000 psu. Thank!

[andyjazz]

so are there equivalents to the 17N80C3's? These things are pretty beefy: 800v, 17A, 208W's. Last i looked they are on back order till Aug. Any help would be greatly appreciated. I'm working on a PMP1000 with no schematic.