I understand that it's a 230V only power supply but the EI-33 transformer is abysmal for anything more powerful than 250W, IMO... though at least we know an EI-33 can do 350W on a 230V input voltage. The power supply as a whole seems less than stellar, but I disagree that the STPS30H100CT would be incapable of 35A... it is a full wave rectified output being a half bridge unit so both diodes in the schottky are fully conducting. It is rated at 30A @ 155*C and the surge non repetitive forward current is 250A for 10ms, in a sinusoidal waveform (at 25*C but still) - it can take some abuse. The maximum temperature rating is 175*C and the voltage drops in the datasheet (at 125*C) don't look too bad either... I think it's capable of the labeled rating. I agree that it's bad practice to use rectifiers rated at a lower current than the label, but still... also, the secondary rectifiers are not completely telling of the real current limits on each rail. The main transformer I think is much more the limiter with windings and transformer taps also having a current limit (as well as a voltage drop along with the rest of the coils) and more controlling of how power is distributed on each output. Also, the combined +12V rating is 28A, not 35A.
I disagree about those 13009s... I think, at least on an 115V input, that TO-220 13009s max out at about 300W without the rest of the PSU being seriously overspec'd and extremely well cooled and ventilated. In TO-3P they may be capable of 350W. Since 230V is more efficient than 115V you managed to get 350W out of them but at 400W it exploded, so... I see a minimum load resistor next to one of those Teapos. That Teapo might get toasty and hatch...
by c_hegge » July 4th, 2013, 3:17 pm 
