Power supply build quality pictorial. part 2

[goodpsusearch]

Re: Power supply build quality pictorial. part 2

Not bad

[maxbarjr]

Re: Power supply build quality pictorial. part 2

I am new here. I was searching for a schematic diagram for an ENERMAX EG651P-V when I came across this forum. Been reading this thread and I found it really interesting. The EG651P is an old PSU, but it's still working. I would like to use it for my ham radio power supply. How can I crank up the +12V to +13.8V? This SMPS is using the LM339N Comparator not the usual TL494 chip.

Looking forward for any help out there.

Thank you in advance.

Max

[momaka]

Re: Power supply build quality pictorial. part 2

@ maxbarjr:
You may want to open a new thread about your ENERMAX EG651P-V, so that people can focus particularly on the questions you have.

Also, although I'm not familiar with the ENERMAX EG651P-V, I'm pretty sure the LM339 is not the main controller. TL494 is just one PWM controller - you may have a 7500 variant, SG6105, UC384x, or some proprietary one. Have a second look and post that info in your new thread. Good pictures are usually helpful too.

@ lti, post #2540:
The output filtering still seems a bit on the low side. But other than that, it doesn't look bad. I see the light-blue ceramic caps are Y2 class, based on their safety logos. So the power adapter may be alright overall.

[maxbarjr]

Re: Power supply build quality pictorial. part 2

Thanks momaka. I will surely do that.

@ maxbarjr:
You may want to open a new thread about your ENERMAX EG651P-V, so that people can focus particularly on the questions you have.

Also, although I'm not familiar with the ENERMAX EG651P-V, I'm pretty sure the LM339 is not the main controller. TL494 is just one PWM controller - you may have a 7500 variant, SG6105, UC384x, or some proprietary one. Have a second look and post that info in your new thread. Good pictures are usually helpful too.

@ lti, post #2540:
The output filtering still seems a bit on the low side. But other than that, it doesn't look bad. I see the light-blue ceramic caps are Y2 class, based on their safety logos. So the power adapter may be alright overall.

[Stefan Payne]

Re: Power supply build quality pictorial. part 2

Annyone know who did this 480W unit?

[kaboom]

Re: Power supply build quality pictorial. part 2

^

I know! I know!

Hacks and Slashers R Us. HSRU.


Those two primary caps aren't even close. They're 820u/200v max.

[momaka]

Re: Power supply build quality pictorial. part 2

Annyone know who did this 480W unit?

Doesn't look like anything I've seen. Do you have the PSU label? Maybe that can give a clue. Otherwise, we need one of the regular PSU experts in here (c_hegge and Pentium4, among others).

That aside, the PSU doesn't look that bad in terms of guts. Just looks hacked together, as kaboom noted. But good enough to fix up for a basic PC, IMO.

[pdavid]

Re: Power supply build quality pictorial. part 2

I have a couple AT psu that has the same style markings on the trafos, plus the unusual heatsinks. If the silkscreen under the main trafo says PCB-xxx than it's the same unknown manufacturer I'm trying to pinpoint for some time now... just for fun.

Just noticed this one says: PCB-360-2

[370forlife]

Re: Power supply build quality pictorial. part 2

Annyone know who did this 480W unit?

The messy but complete design and choice of dodgy components makes me think it is an old Superflower design.

[Stefan Payne]

Re: Power supply build quality pictorial. part 2

The messy but complete design and choice of dodgy components makes me think it is an old Superflower design.

Hm, that's completely possible as the company who did this PSU sold Super Flower PSUs for years. And are still around.

It's a Silentmaxx 480W PSU (IC Tech is also on the label)

Doesn't look like anything I've seen. Do you have the PSU label? Maybe that can give a clue. Otherwise, we need one of the regular PSU experts in here (c_hegge and Pentium4, among others).

It's Silentmaxx 480W unit like this one...

That aside, the PSU doesn't look that bad in terms of guts. Just looks hacked together, as kaboom noted. But good enough to fix up for a basic PC, IMO.

So you'd fix it up and it's safe to use in an older PC and it woudn't explode?
Interesting is that all secondary filtering caps are not flat on the board and 16V/2200uF SamXon.
Didn't expect those in a 2004ish PSU...
I'd expected this unit to be much much worse - like those shitty Topower P4 and P5 things...

Can you say anything about the topology?
Those coils between the primary and secondary side make me wonder.
But it seems like it's an independently regulated unit, is it not?

[momaka]

Re: Power supply build quality pictorial. part 2

It's a Silentmaxx 480W PSU (IC Tech is also on the label)

Okay, nothing familiar there either. The label looks cheap.

So you'd fix it up and it's safe to use in an older PC and it woudn't explode?

Yes.

As long as you fix all of the dodgy work that was done on it (like the flying caps on the secondary side or that polypropylene cap on the solder side), it should be a pretty reliable PSU.

Explode? I highly doubt that. Judging by the dust on the heatsinks, it looks like this PSU has been in service for quite a while. So it's probably going to continue to be a reliable workhorse with some new caps.

Even some Deer PSUs can be quite reliable. Here's an older one I fixed up:
https://www.badcaps.net/forum/showpo...&postcount=490
I've been using it only a few times in the summer every year for the last 5 years. Although very crude, this particular Deer design is dependable with good caps. It even has the dreaded "critical cap" 2-transistor 5VSB. When I found it, the 5VSB was not working right due to bad Rulycon caps. I put some new Chemicon KY caps on the output and replaced the critical 22uF 50V Rulycon with a Panasonic FC, and the 5VSB now reads spot-on 5.00V.

Interesting is that all secondary filtering caps are not flat on the board and 16V/2200uF SamXon.

And GF series

Can you say anything about the topology?
Those coils between the primary and secondary side make me wonder.
But it seems like it's an independently regulated unit, is it not?

Topology is the good old classic half-bridge. (Note that there are 3 transformers, and also the primary has two BJTs.) Obviously not very efficient by today's standards, but it is venerable.

And yes, I think this is an independently-regulated unit as well. Those coils between the secondary heatsink and the main transformer suggest that the 3.3V and 5V rails are probably regulated with a mag-amp circuit. If that really is the case, then this is a rather good PSU and worthy of a recap. If the primary side is designed well, those TO-3P BJTs should be able to deliver 400 Watts no problem. Just make sure to change all of the caps on the 5VSB rail. Looks like a 2-transistor design, though I can't tell with 100% confidence from these pictures. Either way, it would be fine with a recap. No need to change the primary bulk caps, though. Even though they are a crappy brand, it's unlikely they will fail anytime soon.

[Stefan Payne]

Re: Power supply build quality pictorial. part 2

Thanks Momoka!
It seems that the fans may need some oil as well...
The cheapish label was pretty much standard at the time. Even now renowned manufacturers did that back in 2004...

[pdavid]

Re: Power supply build quality pictorial. part 2

It turns out I have some "IC Tech" ATX psu too.

No model or manufacturer on the label. Just plain yellow sticker that says 300W P4 and the voltage specs.

XF-xxx markings on trafos. PCB-225-11 printed on pcb. Made in 2003.

Half Bridge with optional PFC.

And then there is these AT units made in 1992, 1993.

Mystery solved?

[momaka]

Re: Power supply build quality pictorial. part 2

Mystery solved?

mmmmm.... Nope! lol
It just tells us this company has been making PSUs for some time (a good sign, I suppose? ). And it looks like the main topology with the two ICs on the secondary (probably a 494/7500 PWM and 339 quad op-amp) hasn't changed much over the years.

That said, the AT PSU in the last picture you posted is beyond gutless for today's standards. But for an AT system, I guess it isn't that bad, as those don't require much power. Could probably do an honest 50-100 Watts at best, IMO. I wonder what its label claimed, though.

[Behemot]

Re: Power supply build quality pictorial. part 2

Compared to many other AT units from that era, it is actually mediocre at least…

[pdavid]

Re: Power supply build quality pictorial. part 2

Well, whoever makes these they put XF-xxx markings on the trafos.
The guttles AT came with 220uf main caps. The main transformer is some 33mm size with no center tap. 150-180W on a good day I guess. The other, beefier one, has an almost identical layout plus fan controller bolted to the heatsink. As for the labels there is minimal info on them. The AT units both claim 200W.

[goodpsusearch]

Re: Power supply build quality pictorial. part 2

Hec Windmill Pro 385

GBU406 4A bridge rectifier

K3767 5vsb mosfet

UC3843B controller & WT751002 supervisor IC

STP10NK60Z 10A continuous MOSFET

S7912PI for -12V

STPS30H100CT 30A schottky rectifier for 12V

STPS4045CW 40A for 5V

MBR3045PT 30A rectifier and 09N03LA 50A power transistor for 3.3V

[Stefan Payne]

Re: Power supply build quality pictorial. part 2

Hm, interesting. Haven't seen much of this unit before.

Do you know what those black caps on the secondary side with the 3 indents are?

[ReeceyBurger123]

Re: Power supply build quality pictorial. part 2

Hm, interesting. Haven't seen much of this unit before.

Do you know what those black caps on the secondary side with the 3 indents are?

They are Fuhjyyu I recapped a Hec that had Fhujyyus in a while ago.

[goodpsusearch]

Re: Power supply build quality pictorial. part 2

Hm, interesting. Haven't seen much of this unit before.

Do you know what those black caps on the secondary side with the 3 indents are?

It's almost identical to this:
https://www.badcaps.net/forum/showthread.php?t=34170

They are Fuhjyyu I recapped a Hec that had Fhujyyus in a while ago.

Nope. The black caps are Suscon SK and DON caps