ebay power supply

[Kn8]

Hi I would be interested in joining in on a group buy and will be happy to purchase four supplies at the right price.
Ivan.

[HankMcSpank]

Hi I would be interested in joining in on a group buy and will be happy to purchase four supplies at the right price.
Ivan.

Once again...due to the weight of these, I reckon a 'group buy' will only work if people can collectin person, from North/Central London. In other words, the win here is mainly the £10 saving he's charging on the P&P ...by grouping these PSUs in blocks of 25kg, then some useful saving can be made on the P&P (plus whatever discount he offers on volume)

I've now emailed the seller for price break points. (but like I say, not worth pursuing unless the voltage output on these PSUs can be tamed to more usable levels)

[HankMcSpank]

I,ve just been quoted £16.00 Del for 3 of these to yorkshire from the seller and they are on there way as we speak.

Mental!

Forget group buys. ....we may as well all fly solo with that kind of offer - stupid price!!!

[irving2008]

Mental!

Forget group buys. ....we may as well all fly solo with that kind of offer - stupid price!!!

I paid £19 del for 2, so £22.49 a PSU... cant be bad...

It may take me a couple of days to work out the answer to the volts. Its a TI UCC2985 phase-shifting PWM controller driving 4 x F740 500V 20A HexFETs in a full-bridge, running at 340vDC supply, driving the output transformer, the output being rectified by two BYT16P dual fast 20A rectifiers. Feedback from output to PWM is via a pair of opto-isolators. As such it is not far different to the reference circuit for the 2985 PWM but so far not been able to identify the actual voltage regulation mechanism.

There are a pair of FA3624 PWM controllers on a daughter board each driving an FP460L hexfet as a single ended flyback converter to provide logic voltages of 5v and 12v (I'm guessing based on the other chips around there, but it would seem logical).

There is another daughter board with SMT parts on that is made in UK (rest is made in Germany) which suggests this was bought in. Havent been able to fathom its purpose yet.

[Tom]

TI UCC2985 phase-shifting PWM controller driving 4 x F740 500V 20A HexFETs in a full-bridge, running at 340vDC supply, driving the output transformer, the output being rectified by two BYT16P dual fast 20A rectifiers. Feedback from output to PWM is via a pair of opto-isolators. There are a pair of FA3624 PWM controllers on a daughter board each driving an FP460L hexfet as a single ended flyback converter to provide logic voltages

Crikey! I'll just be happy if I manage not to set fire to it when I plug it in!!
Thanks for the investigations Irving - i've got a couple more weeks of fiddling with leadscrew and alignment then I think I'll suck it and see what happens at 42V. (unless your reverse engineering gets finished before my machine)(possible)

PS. cheers for the ebay spades link Hank - i'm nowhere near Maplin :(