Thermaltake TR2-500 Primary cap bad?

[momaka]

Re: Thermaltake TR2-500 Primary cap bad?

I doubt if the boost circuit would have caused the bleed resistors to fail, though.

Yeah, I doubt it too. I didn't even notice the bit about the failed bleed/balance resistors, though. Yes, if they fail, they may cause the voltage across the caps to shift from one cap to the other, thus possibly over-volting one of the caps slightly.
Not sure why they failed, either. I've seen high resistance resistors like that fail for no reason before, though.

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

That voltage boost circuit is the definition of crap. The caps are going to drain even if they put Rubycon 105°C in there. Too much heat. Why spend money on that circuit (resistors, diodes and capacitors) when it is not going to last more than a couple of months? My theory is that they do this to trick reviews about efficiency.

Removing the caps was the first thing to do to disable that circuit. The caps were Teapo, completely dead as expected.

Not sure why they failed, either. I've seen high resistance resistors like that fail for no reason before, though.

Where were the failed resistors?


Out of curiosity I checked the bleeding resistors of more than 15 power supplies (fortunately I take pictures of every psu I open) and they all had values ranging from 150kohm to 250kohm. A Konig power supply had 1000kohm resistors! The only exception was the Jou Jye psus, that had 65kohm resistors. But those resistors were clearly of higher watts than the others, 1/2watt probably.

I assume that the 100kohm 1/4watt bleeding resistors of that Thermaltake were quite on the low side.

240AC*1.41=339V

339V/2=170V

(170^2)/100000 = 0.289W

0.289W is more than the maximum allowed 0.25W those resistors are rated. The voltage boost circuit might have made things even worse.

I hope the problem is solved with the 180kohm resistors I put.

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

I got the replacement caps I ordered!

2x1000uF 200V Panasonic UQ

With the new primary caps installed I get 162.5V across each capacitor.


I modded the fan controller circuit to make the psu run cooler.

I put a 9.1kohm resistor in parallel with the thermistor, as you can see in the last picture. The psu has not been tested yet with a PC, so I cannot be sure about its impact on the fan controller.

I want to thank everyone for your help and support.

[ben7]

Re: Thermaltake TR2-500 Primary cap bad?

I got the replacement caps I ordered!

2x1000uF 200V Panasonic UQ

With the new primary caps installed I get 162.5V across each capacitor.


I modded the fan controller circuit to make the psu run cooler.

I put a 9.1kohm resistor in parallel with the thermistor, as you can see in the last picture. The psu has not been tested yet with a PC, so I cannot be sure about its impact on the fan controller.

I want to thank everyone for your help and support.

Good job as always!

Cheerz

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

The fan mod failed.

The 9.1kohm resistor made the fan run full speed after some minutes of normal PC use. I tried 10Kohm but it was pretty much the same.

Since I don't have bigger resistors laying around and the psu doesn't run very hot I let the fan controller unchanged.

[c_hegge]

Re: Thermaltake TR2-500 Primary cap bad?

I found a similar thing with the CWT branded version that now power's my brother's PC. I left the can controller unmodified, and it still doesn't run that hot.