Corsair GS800 Power Supply Problem

[R_J]

Re: Corsair GS800 Power Supply Problem

The ZD is a PBSs5350t, here is the pinout. I suspect the transistor is shorted emitter to collector, that would explain why the ps won't turn off.
W = made in China
19 = date code

[ShortCircuited]

Re: Corsair GS800 Power Supply Problem

It must be Q12, again its hard to make out the numbers sometimes, So it's collector connects to pin5 (pin 3 is not connected, correct? so I am counting from the same direction)
So does Q12 emitter connect to the VCC supply? if it does, check that it is not shorted, if it is shorted it would never turn off the vcc to the cm6800.
Got a number on Q12?

Yes, pin 3 on riser board is NC and the 5th pin is the one next to (left) the one that is circled on the silkscreen. Top-Pin to Q12 (emitter?) (ZDW 19) connects to Vcc on cm6800.

Top/middle pin of Q12 and the bottom-right pin is 2 ohm. Short? The bottom-left pin does not seem to be connected to the other two pins on Q12 in the off state-simple continuity check. I do not have a valid spec sheet on Q12/ZDW 19 so I cannot speak specifics on it.

[R_J]

Re: Corsair GS800 Power Supply Problem

It must be Q12, again its hard to make out the numbers sometimes, So it's collector connects to pin5 (pin 3 is not connected, correct? so I am counting from the same direction)
So does Q12 emitter connect to the VCC supply? if it does, check that it is not shorted, if it is shorted it would never turn off the vcc to the cm6800.
Got a number on Q12?

[ShortCircuited]

Re: Corsair GS800 Power Supply Problem

Ok, so that 5th pin could be the vcc supply? On Q2 it seems the base connects to the U3 opto, does Q2's emitter pin connect to hot ground?

It looks like Pin 13 on the CM6800, which is Vcc that runs to pin 5 on the riser card and off to U3(top-right) primary side of course. Only thing on the riser board between IC 6800 and pin 5 is a 0 ohm SMD.

Q2.... you mean Q12....about an inch above U3 (on/off OC) primary side? Q2 is just above the fan header I annotated before. I will look into specs on Q12 and see what is going on with it.

[R_J]

Re: Corsair GS800 Power Supply Problem

Ok, so that 5th pin could be the vcc supply? On Q2 it seems the base connects to the U3 opto, does Q2's emitter pin connect to hot ground?

[ShortCircuited]

Re: Corsair GS800 Power Supply Problem

OK I desoldered that 5th pin (runs to U3/PC1 top-right pin) on the riser card on primary side and it did power off. I feel like that is progress. So that riser card/CM6800 is sending power on signal in err. It did not boost primary side (160ish volts) and secondary side did not power on.....I did not check stand-by voltage though. Id dint want to leave it on and mess it up.


Now with that off can I safely test the secondary power on signal to U3 pin 1?

I will look through photos and see.

[R_J]

Re: Corsair GS800 Power Supply Problem

They must control that baord, because the pfc and the main supply need to be turned off in standby.

After looking at the CM6800 datasheet, I wonder if they controll the VCC line to the CM6800?
Did you take any pictures of the riser board with the ic? It would be nice to know which pins of the ic connect to which pins on the riser board.

[ShortCircuited]

Re: Corsair GS800 Power Supply Problem

Well something turns it on and off, and that's the only way I can see it being controlled, so there might also be a problem on the primary side as well. U3 seems to connect to (Q2?) which then connects to the primary control module, This is not a simple power supply.

On the primary side OC U3/PC1 traces to that 10-pin riser board ( 5th pin from the right which contains a CM6800, which I did replace. maybe I could desolder this and see if it powers off?

[R_J]

Re: Corsair GS800 Power Supply Problem

I ordered some Wt7502s a few weeks ago....will be a few more weeks though.

I pulled a leg on the jumper to 7502 then grounded the trace to the OC (U3/PC1) and it did not power off (green ungrounded).

Well something turns it on and off, and that's the only way I can see it being controlled, so there might also be a problem on the primary side as well. U3 seems to connect to (Q2?) which then connects to the primary control module, This is not a simple power supply.

[R_J]

Re: Corsair GS800 Power Supply Problem

just ground out the jumper going to pin2 of the opto, that will turn ON the internal led (the 220Ω) on pin1 is the current limiter from the +5v for the opto.
At some point the wt7502 does control this line.
The way I think it worksis:
When first pluged in, the main power supply turns on for a second and outputs the +12v, +5v & +3.3v, IF they are correct, then PGI goes high and FPOB goes low turning off the main supply, When PSONB goes low, FPOB goes high turning ON the main power supply again. Or I could be wrong.

[ShortCircuited]

Re: Corsair GS800 Power Supply Problem

I ordered some Wt7502s a few weeks ago....will be a few more weeks though.

I pulled a leg on the jumper to 7502 then grounded the trace to the OC (U3/PC1) and it did not power off (green ungrounded).

There is certainly an odd sound coming from U5 opto. when you touch the probe to it either terminal on the secondary side it makes a significant buzzing noise

[R_J]

Re: Corsair GS800 Power Supply Problem

I reinstalled already.

You could unsolder pin3 or remove what looks like a jumper wire from pin 3 that connects to theat trace back to the opto.
Did you ever replace the wt7502?

[ShortCircuited]

Re: Corsair GS800 Power Supply Problem

I could'nt make out the designations from the picture so I made my own. So U3 must control the power supply on/off, but it looks like it is controlled by the wt7502 if it only connects to it's pin3.
If you still have the wt7502 removed, if you ground the pin3 trace does the power supply turn off?

I reinstalled already.

[R_J]

Re: Corsair GS800 Power Supply Problem

I could'nt make out the designations from the picture so I made my own. So U3 must control the power supply on/off, but it looks like it is controlled by the wt7502 if it only connects to it's pin3.
If you still have the wt7502 removed, if you ground the pin3 trace does the power supply turn off?

[ShortCircuited]

Re: Corsair GS800 Power Supply Problem

U3:
PC1-Pin 1 trace:...220ohm resistor (straight down on board)...purple wire (+5vsb voltage)
PC1-Pin 2 trace:.......FPOB; WT7502 Pin 3

U5:
PC2-Pin 1 trace:750 ohm SM...2200ohm SMD*...U6 (Adjustable Regulator TO-92) (UTC TL431K PCR)
PC2-Pin 2 trace: U6 regulator (pin3-10.7v)

Voltage

PC1: Grounded/Ungrounded:
Pin 1: 5.067/5.067
Pin 2: 5.6/5.6


PC2: Grounded/Ungrounded
Pin 1: 11.7/11.7
Pin 2: 10.7/10.7



*Circuit branches off here into the sunset.

[R_J]

Re: Corsair GS800 Power Supply Problem

If you remove the feedback by removing the optocouplers you risk BLOWING UP THE POWER SUPPLY!
The voltage on one of the pins of PC1 should change when the power supply is switched on and off (by grounding the wire) I will guess that either pin 1 or pin 2 of pc1 is connected to 5 volts and the other pin will be controlled by a transistor, and when that other pin is taken low, the optocoupler led will light.
So trace back pins 1&2 of PC1 and see what they are connected to, I can't make out the traces in that area from the picture.

[ShortCircuited]

Re: Corsair GS800 Power Supply Problem

No change in voltage when the on/off wire is grounded vs. ungrounded on the secondary (diode) side of the OC. OC closest to the main transformer is 10.7/11.8 and the adjacent (under J22) is 4.6/5.0v grounded and ungrounded. When I briefly desoldered all 4 pins of those two OCs that should have cut the LED signal to the primary side and turned PS off? If i can cut the on signal on secondary side and it powers off I could better isolate the problem.

[R_J]

Re: Corsair GS800 Power Supply Problem

The one optocoupler by itself is likely for feedback regulation for the standby 5v. The other two, the closest one to the transformer is for regulation for the main +12,+5 etc. The one next to it, should be for turning the power supply on and off. The fault might not be with the optocoupler but could be either on the secondary side, not controlling the opto, or on the primary side, not switching the primary on and off.

You do not want to disconnect the feedback optocouplers, without the feedback (and regulation) the power supply could cause the secondary voltages to very high and cause damage.

When you open or ground the power ON pin, the voltage on the (on/off) optocoupler (led side) should change.

[ShortCircuited]

Re: Corsair GS800 Power Supply Problem

It has three optos. One of the two optos closest to the main transformer is making a weird buzzing noise that elevates significantly when checking voltage on the secondary side of the opto. The adjacent opto does is not affected by a voltage check and does not buzz. I changed the one closest to the transformer and the buzzing is the same with the new opto. I also desoldered the two terminals (secondary side) to this buzzing opto and it was still on.

EDIT: Briefly desoldered both OCs closest to the main transformer (secondary side only) and it is still running.

[R_J]

Re: Corsair GS800 Power Supply Problem

Thats because the WT7502 has nothing to do with turning the power supply on and off. Altjough it might for protection. There are a pair of optocouplers side by side, one will be for the primary regulation, and the other is likely for turning the power supply on and off. I believe the optocoupler for power on/off is the one below the printing J22