I do this mostly for fun and the challenge, I usually build DIY amplifier for HiFi use, but occasionally buy som repair items in the Pro audio segment. I use them in my PA system that i'm slowly building.
This has become a puzzle, although it might look like the transformer is the answer this time. But i will work/test trough the rest of the PS just to be sure.
I have a variac at hand and always use it when testing I don't like blowing stuff up, it's so expensive :S

God tip about the output modules Have not done thorough testing there, just some quick measurements, and didn't find any thing that looked strange. Will check them closer before connecting them to the PS.

 

Hi, sorry to jump on this thread like this. I have a p7000s that seems to have some kind of overheating problem (I could be wrong though). It works perfectly for a while (conditions vary depending on whether it's rack mounted, standing alone or running while open. Shortest being when mounted with other stuff) then suddenly goes off-no temp or protection light. It comes right back on after switching it on and off, but then the time before it goes off again isn't too long. I've tried it with different cables and speakers with the same result. I've seen the output fans come on once or twice but never for very long (i dont think i get the unit hot enough). Things i have noticed are that relay (RY401) and resistors R451 and R416 have been replaced with an omron G4A-1A-PE and two STM Cl-40s. Additionally, the heatsink holding MOSFETs Q407 & Q406 gets too hot to touch very quickly (10minutes) even when in idle. I have another similar unit that only gets warm to the touch at that heatsink.

I took it to an electrician to have a look at but he couldn't replicate the problem and so he didn't want to fiddle around. I'm hoping you guys can help me out with some troubleshooting ideas? It would be much appreciated. The unit is around 5 years old.

 

Have you measured the AC line voltage?
In my unit there where several bad Capacitors (The small value ones of Samxon brand) in the Power supply section. Q407 - Q406 do they have the original part number? It should be IRG4PC50U as listed in the service manual.
What kind of speakers do you run, low ohm?

 

Have you measured the AC line voltage?
In my unit there where several bad Capacitors (The small value ones of Samxon brand) in the Power supply section. Q407 - Q406 do they have the original part number? It should be IRG4PC50U as listed in the service manual.
What kind of speakers do you run, low ohm?

Hi, yeah, the AC line voltage is fine. I usually check the voltage before i plug in Just got a good look at the MOSFETs. They're also not the originals. They're G4PH50UD. Not sure if those are okay for this unit. I run a pair of EV tx1152's (they're 8ohm)

 

Thread is getting too complicated.
Hijacking is not encouraged.
Mods please split this thread