Behringer Europort EPA300 burning fuse

[landofshqiponja]

hello all!

I have a Behringer EPA300 (europort) that the second it gets powered burns the fuse.   

Someone has repaired the system previously, unfortunately I don't remember what the problem was or what was repaired. 

The repair man I took it to now to figure out why the fuse keeps burning told me that without a schematic of the board, he cannot fix it as someone has previously repaired it in the wrong way.

Does anyone know where I can download a schematic of the motherboard?

Thanks so much!

[darkspr1te]

I've repaired quite a few behringer products  so some tips.


if primary fuse blowing then issue is in psu side of the system ,
see the manual for epa 900 found here :-
https://music-electronics-forum.com/forum/schematic-requests/42466-please-please-help-me-with-behringer-smpsu-19-power-supply
and here for epa300 i think (dont have one, cant confirm)
https://www.electronica-pt.com/esquema/audio/behringer-audio/behriner-smpsu18-27413/

it's a SMPS thats also used in the XENYX series mixers too but board layout is different i would guess.
i often seen the psu to be on a connector so hope the techie did the first rule and check voltages.

it is common for the IRF460 in the PSU to fail ,dont forget the isolator when replaced.
check all caps for looseness , as a music equipment manufacturer they tend to not glue blob the large caps nor do they often glue connectors.

input bridge rectifier also fails often as the designers cramp it in close to the heatsinks , in some units i've had multiple fails so we ended up remote mounting the diode pack and bolted to to metal (electrically isolated but heat sinked)

cap failures from heat/drying up and bad solder joints also common, so if you hack crackles and pops then check the board for swelled caps or leakage, and also while running tap the equipment to test for the poor solder joint (very very common on portable tech)

well good luck

darkspr1te