Re: Thermaltake TR2 750W -fixed 5v stby now +5v reads low and no 12v FIXED
Thank you all for the replies.
I could fix it!
There were two problems after I fixed the 5V stby rail.
1 - I damaged the PS223 by installing it backawards
2 - I broke my thermaltake power supply tester during the tests, so the start button in it won't start the PS.
This one was very difficult to pinpoint since I thought that the fault was in the power supply, not in the tester
rodd
New Member
Last Activity: 10-14-2023, 02:13 PM
Joined: 02-14-2021
Location: Rio de Janeiro
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Re: Thermaltake TR2 750W -fixed 5v stby now +5v reads low and no 12v
I installed the IC backwards, that's why.
After I replaced another dried capacitor, al volatges are ok, but the PSU does not start if I install a new IC in the correct position...Leave a comment:
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Re: Thermaltake TR2 750W -fixed 5v stby now +5v reads low and no 12v
Hi,
More news from the "front".
I inslalled the PS223 backwards again and the PS starts and all the voltages are ok.
This means that the CM6800 and all "power semiconductors" are ok.
So I guess that the problem is located on the small pcb where the PS223 is installed.
As I asked in my previous post, I do not understand very well how the PS223 works but it seems that installing it bacwards causes the ok signal to be present.
I have already checked every resistor...Last edited by rodd; 08-18-2023, 09:33 AM.Leave a comment:
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Re: Thermaltake TR2 750W -fixed 5v stby now +5v reads low and no 12v
These are photos from top and bottom.
The heatsink with the rectifier diodes of the secondary has been removed so I could check them out of the circuit....Leave a comment:
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Re: Thermaltake TR2 750W -fixed 5v stby now +5v reads low and no 12v
Hi,
I did not mean to offend anybody, I have just described what I have done and my observations.
After I fixed the +5V Stby, the PS could start but the PS monitor I used was beeping.
Checking its display I could see that the +12v and +5V was showing LL, but 3.3V rail was ok.
So my line of thought is that the main oscillator is working.
However if the 5V and 12v rails voltages are low the PS223 should have turned the main oscillator off.
This IC is mounted on a small...Last edited by rodd; 08-13-2023, 09:10 AM.Leave a comment:
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Re: Thermaltake TR2 750W -fixed 5v stby now +5v reads low and no 12v
After fixing the +5V Stby and replacing the CM6008 the voltage across the main cap raised from 175V to 385V, so I guess that the PFC section is working fine.
Is there any other thing I should check?Leave a comment:
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Thermaltake TR2 750W -fixed 5v stby now +5v reads low and no 12v
Dear all,
I am trying to repair the ATX power supply.
First I fixed the +5V stby, which was zero due to a shorted TNY279 and an open 2R2 resistor.
Just in case I replaced the PWM control IC (PS223) and the PFC control IC (CM6800).
Now the supply turns on, the +3.3V is fine, but the +5V measures only 2.5V and there is no +12V.
I have checked every diode I could find with a DMM (in circuit) and all the capacitors (in circuit) no shorts, low ESR.
In despair I removed the low voltage diodes which were all mounted on the same heatsink... -
Re: New Members - please post your introductions here
Hi folks.
Retired electronics hobbyist who likes to fix broken things.Leave a comment:
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