"Delta Power" MAX-500ATX 450W power supply (not real Delta)

[etnietering]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

Look much better to me!

I have some more upgrades in the works for my logisys (once my 60W soldering iron and oscilloscope come in ): upgrading the secondary side schottky packs (they're significantly underrated) and adding my delayed fan turn off controller thing from my other thread. I got a ton of schottkys from ON Semiconductor for really cheap. You can get up to 10 different components (max of 5 or 10 of each) for 11 dollars shipping and handling. So for 11 bucks I got 60 schottky packs, 5 30A 450V NPN switchers, and 30 linear voltage regulators. Not bad! The NPNs are almost 4 bucks apiece, if you were to actually buy them!

[370forlife]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

Look much better to me!

I have some more upgrades in the works for my logisys (once my 60W soldering iron and oscilloscope come in ): upgrading the secondary side schottky packs (they're significantly underrated) and adding my delayed fan turn off controller thing from my other thread. I got a ton of schottkys from ON Semiconductor for really cheap. You can get up to 10 different components (max of 5 or 10 of each) for 11 dollars shipping and handling. So for 11 bucks I got 60 schottky packs, 5 30A 450V NPN switchers, and 30 linear voltage regulators. Not bad! The NPNs are almost 4 bucks apiece, if you were to actually buy them!

HOW TO DO THIS?

[etnietering]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

you have to make a 'myON' account, then when you find what you want, click on 'samples' (not all parts are available for samples) and then you collect them in your cart. Then when you're done you click check-out and put in your info (you have to make up a company), and they send it to you, real speedy fed-ex

[370forlife]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

you have to make a 'myON' account, then when you find what you want, click on 'samples' (not all parts are available for samples) and then you collect them in your cart. Then when you're done you click check-out and put in your info (you have to make up a company), and they send it to you, real speedy fed-ex

This could be useful information...

[ratdude747]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

not bad. that is probably one the worst units i have seen. the heatsinks are better than the worst which had flat aluminum plates with no fins or stamps, or bends.

why the new fan? id use the old one until it died and then replace it.

[370forlife]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

Ya, but what would happen when it died and you weren't in the room to know it...

[Newbie2]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

The fan was generic and I assume it is a low-quality sleeve bearing fan, and this power supply was in use before, so I guessed that the original fan didn't have much life left in it and replaced it.

It is just a backup power supply that won't see regular use, but if it does need to be used then it's better to be safe than sorry.

[ratdude747]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

good point. but ANY part could do that

[Newbie2]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

good point. but ANY part could do that

At least there's not as high of a chance of the fan failing. If the fan failed the little heatsinks I guess won't be able to sufficiently dissipate the heat generated by the primary and secondary side components, and lead to early failure.

[370forlife]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

you have to make a 'myON' account, then when you find what you want, click on 'samples' (not all parts are available for samples) and then you collect them in your cart. Then when you're done you click check-out and put in your info (you have to make up a company), and they send it to you, real speedy fed-ex

Heres what I got

MBR4045WTG 40 A, 45 V Schottky Rectifier
MBR6045WTG 60 A, 45 V Schottky Rectifier
MBRF30L45CTG 30 A, 45 V L-Series Schottky Rectifier
MBR3045PTG 30 A, 45 V Schottky Rectifier
MBR60L45WTG 60 A, 45 V L-Series Dual Schottky Rectifier
MJW18020G Bipolar Power NPN, 30 A, 450 V
MJE5852G Bipolar Power PNP, 8 A, 400 V
MBR7030WTG 70 A, 30 V Schottky Rectifier
MBR60L45CTG 60 A, 45 V L-Series Schottky Rectifier
MBR40L45CTG 40 A, 45 V L-Series Dual Schottky Rectifier

the reason I got so many similarly rated ones is because some are TO-247, which can dissipate heat better because of larger surface area, and others are TO-220, which a lot of cheaper psu's aren't silkscreened for the larger lead spacing of the TO-247.

[etnietering]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

Nice! the TO-247s are huge! You'll need to get some type of thermal pads to electrically isolate them from the heatsinks - otherwise you're in trouble.

And yeah, a fan failure can cause a cascade of other failures...good fannage is important

[370forlife]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

ya, I have a ton of the 30A, 45V TO-247's from propriatary dell newton and lite-on psu's, as well as a huge pile of the thermal pads that go with them.

You can also get to-247 thermal pads on digikey in a pack of 100 for $0.41, and 100 to-220 pads for $0.22, which I just might.

[linuxguru]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

Check out the voltage specs on the 6N60 - it's probably not as high as the 2N60, which is good enough for the auxiliary flyback. Likewise, 13007 BJTs and the original secondary rectifiers are also good enough. Everything else seems fine.

[370forlife]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

Check out the voltage specs on the 6N60 - it's probably not as high as the 2N60, which is good enough for the auxiliary flyback. Likewise, 13007 BJTs and the original secondary rectifiers are also good enough. Everything else seems fine.

The parts on the secondary at least are probalby no where near 450W, but probalby really pushing it for 300W, and their labeled ratings are probalby what they can do at 25C. Heat em up to 40C and you are probalby looking at 2/3 the capacity as at 25C. Thats why its good to overbuild them. Also puts the voltages more closer to their specs. Thats why the allied 500W on the JG review kept the 5v at 5.1 until just before it puked its guts out, it had 60A of capacity for it.

[everell]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

I can understand why you changed the 13007 switching transistors to 13009. But I don't understand the need to change the 2N60 2A transistor to a 6A transistor.

The 2N60 transistor is one of two transistors in the 5vsb circuit. Two amps at 320 volts should be plenty for anything the 5vsb circuit is going to do. But a 6 amp transistor????? What about the little black transistor next to it that drives it? Will it be able to handle the extra drive power requirements? And will that itty bitty 5vsb transformer be able to accomodate the extra current capability?

I am eyewitness to what happens when the 5vsb circuit EXPLODES and puts chunks of transistor into orbit!

[370forlife]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

I know in my yuelin when I changed that 3rd transistor on it's heatsink to the 6A one from the CWT, it just blew the fuse. Not just popped it, but blew it. I put the original 2A back in, and it fired right up. There was no shorts or anything.

I wonder why it worked for this sunpro?

[Newbie2]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

I know in my yuelin when I changed that 3rd transistor on it's heatsink to the 6A one from the CWT, it just blew the fuse. Not just popped it, but blew it. I put the original 2A back in, and it fired right up. There was no shorts or anything.

I wonder why it worked for this sunpro?

Do you know what the model numbers are for the original transistor and the transistor that came out of the CWT?

I can understand why you changed the 13007 switching transistors to 13009. But I don't understand the need to change the 2N60 2A transistor to a 6A transistor.

The 2N60 transistor is one of two transistors in the 5vsb circuit. Two amps at 320 volts should be plenty for anything the 5vsb circuit is going to do. But a 6 amp transistor????? What about the little black transistor next to it that drives it? Will it be able to handle the extra drive power requirements? And will that itty bitty 5vsb transformer be able to accomodate the extra current capability?

I am eyewitness to what happens when the 5vsb circuit EXPLODES and puts chunks of transistor into orbit!

I didn't know that the 2N60 MOSFET was for the +5VSB circuit, if I knew then I wouldn't have upgraded it.

It does work though, and I already have it in there. I don't think it will decrease reliability, since it's just a higher-rated MOSFET.

[momaka]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

I didn't know that the 2N60 MOSFET was for the +5VSB circuit, if I knew then I wouldn't have upgraded it.
It does work though, and I already have it in there. I don't think it will decrease reliability, since it's just a higher-rated MOSFET.

Read everell's post again.
What he's saying is that when you put a higher-rated MOSFET, you also need more current to turn it on. But if the small transistor that drives this higher-rated MOSFET can't provide enough current, then it could either overheat and die or the MOSFET just won't be fully turned on (which means poor efficiency and more heat - if I remember correctly, MOSFETs are most efficient when either fully on or fully off). I think I read this somewhere else as well.
So overall it is possible to decrease the reliability.

The parts on the secondary at least are probalby no where near 450W, but probalby really pushing it for 300W, and their labeled ratings are probalby what they can do at 25C. Heat em up to 40C and you are probalby looking at 2/3 the capacity as at 25C. Thats why its good to overbuild them.

These cheap power supplies were never meant to do anything over 300 watts, so no matter what you put on the secondary side, they'll just blow up.

In fact, this is exactly what many cheap manufacturers do - they look at how much each schottky diode on the secondary can handle, then they calculate the wattage for each rail, add them up and slap that number on the label - and that's just wrong.

What should be done instead is look at how much the primary side can handle and write that wattage on the label. From there, they can overbuild the secondary as much as they like, just as long as they state that the wattage for all the rails cannot combine or exceed over the rating for the primary.

Of course if those manufacturers did that, all these cheap power supplies will have a rating of no more than 250 watts. From a sales point of view, it makes much more sense to put an astronomically-high value on the label and call it "peak" or "max" power.

[Newbie2]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

Read everell's post again.
What he's saying is that when you put a higher-rated MOSFET, you also need more current to turn it on. But if the small transistor that drives this higher-rated MOSFET can't provide enough current, then it could either overheat and die or the MOSFET just won't be fully turned on (which means poor efficiency and more heat - if I remember correctly, MOSFETs are most efficient when either fully on or fully off). I think I read this somewhere else as well.
So overall it is possible to decrease the reliability.

The new P6NK60Z MOSFET I installed has a lower RDS(on) than the original 2N60 MOSFET, 1Ω vs. 5Ω. The gate source voltage (VGSS) of both parts are the same, ±30V. The typical input capacitance (Ciss) on the P6NK60Z MOSFET is higher than the 2N60, 905pF vs. 270pF, but this shouldn't affect performance by very much.

I think the 6A MOSFET, while very overkill, should be fine.

[i4004]

Re: "Delta Power" MAX-500ATX 450W power supply (not real Delta)

>Any more comments?

it's peculiar to put godo components to these crap psus.
nest up it'll blow the main switcher, then you swap that too.
after that transformer will melt, will you fix that too?
hehe...you get the point...

what you did helps it somewhat, but only real help for it is garbage dumpster.