Thermaltake TR2-500 Primary cap bad?

[ben7]

Re: Thermaltake TR2-500 Primary cap bad?

I took out the Capxon primary caps and took more photos of that power supply trying to figure out why the primary capacitor in that specific spot keeps failing.

There is some burnt glue on that bleeding resistor if I am correct. I don't remember those resistors to get hot.

I also consider the possibility of the MOV getting hot, but is that possible?

My last suspect is PPFC placed near the primaries. Do they get hot usually? Is it normal or a sign of failure?

Meanwhile I had a look at the other parts of that power supply.

The bridge rectifier is a 10A KBU10J.

The PWM IC is UC3845B.

The power supply uses C5353 NPN transistor on 5vsb and 2x W14NK50Z power mosfets rated for 14A continuous at 25°C and 7.6A continuous at 100°C.

Now let's move to the secondary section:

-5vsb: 1x 1N582 3A, 2x 1000uF 10V Teapo SC 8x20mm, ripple 1080, esr 0.065

-3.3V: 1x STPS3045 30A,
1x 3300uF 10V Teapo SEK general purpose 10x25mm, ripple 950 and 1x2200uF 6.3V Teapo SC 10x20mm, ripple 1220, esr 0.051

-5V: 2x STPS3045 30A(60A total),
1x 3300uF 10V Teapo SEK general purpose 10x25mm, ripple 950 and 1x2200uF 6.3V Teapo SC 10x20mm, ripple 1220, esr 0.051

-12V: 1x STPS3045 30A, 2x 2200uF 16V Teapo SC 10x30mm, ripple 1780, esr 0.032

- -12V: 1x 470uF 16V Teapo SEK general purpose 8mm

Teapo SEK datasheet
Teapo SC datasheet

The fact that they used GP caps explains the relatively high ripple those Thermaltake psus show when high loaded.

Put two good caps in there for a moment, and power it on. Take note of the voltage across each primary cap. Occasionally, if there is a problem with the PSU, one cap will have a higher voltage across it that the other, sometimes enough (greater than 200v) to cause it to fail.

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

I took out the Capxon primary caps and took more photos of that power supply trying to figure out why the primary capacitor in that specific spot keeps failing.

There is some burnt glue on that bleeding resistor if I am correct. I don't remember those resistors to get hot.

I also consider the possibility of the MOV getting hot, but is that possible?

My last suspect is PPFC placed near the primaries. Do they get hot usually? Is it normal or a sign of failure?

Meanwhile I had a look at the other parts of that power supply.

The bridge rectifier is a 10A KBU10J.

The PWM IC is UC3845B.

The power supply uses C5353 NPN transistor on 5vsb and 2x W14NK50Z power mosfets rated for 14A continuous at 25°C and 7.6A continuous at 100°C.

Now let's move to the secondary section:

-5vsb: 1x 1N582 3A, 2x 1000uF 10V Teapo SC 8x20mm, ripple 1080, esr 0.065

-3.3V: 1x STPS3045 30A,
1x 3300uF 10V Teapo SEK general purpose 10x25mm, ripple 950 and 1x2200uF 6.3V Teapo SC 10x20mm, ripple 1220, esr 0.051

-5V: 2x STPS3045 30A(60A total),
1x 3300uF 10V Teapo SEK general purpose 10x25mm, ripple 950 and 1x2200uF 6.3V Teapo SC 10x20mm, ripple 1220, esr 0.051

-12V: 1x STPS3045 30A, 2x 2200uF 16V Teapo SC 10x30mm, ripple 1780, esr 0.032

- -12V: 1x 470uF 16V Teapo SEK general purpose 8mm

Teapo SEK datasheet
Teapo SC datasheet

The fact that they used GP caps explains the relatively high ripple those Thermaltake psus show when high loaded.

[dmill89]

Re: Thermaltake TR2-500 Primary cap bad?

This psu doesn't have active pfc. As far as I know passive PFC doesn't boost voltage neither stresses the cap.

It doesn't boost voltage but the PFC coil can get rather hot and since this PSU (like most CWTs) has the coil right next to the primary caps this adds additional stress. Of course the primary heatsink on the other side of the caps gets hot when the PSU is loaded and the airflow is somewhat restricted in this area which is somewhat narrow with relatively large objects on both sides that block airflow, the PFC coil being a solid object isn't exactly good for airflow.

[ben7]

Re: Thermaltake TR2-500 Primary cap bad?

Power up the PSU with good caps and see if the voltage across them is [roughly] the same. If they are not, then that is what caused the cap to bulge.

You live in greece, so I beileve your power is 220v. That gets rectified and put across the two capacitors in series. If the voltage across them is uneven, one could possibly blow up (worst case would be about 300v across a 200v cap)

[tom66]

Re: Thermaltake TR2-500 Primary cap bad?

The cap will still be under stress from the AC input ripple. If anything, active PFC is *kinder* as the current is typically sinusoidal, and the actual RMS current is lower than a non-PFC supply. Though in active-PFC designs, the cap is usually smaller, so its ripple current rating is lesser...

[Pentium4]

Re: Thermaltake TR2-500 Primary cap bad?

This psu doesn't have active pfc. As far as I know passive PFC doesn't boost voltage neither stresses the cap.

Ohhh yeah, you're right. Good catch.

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

I wouldn't use CapXon caps as primaries in a PSU with PFC

This psu doesn't have active pfc. As far as I know passive PFC doesn't boost voltage neither stresses the cap.

[Pentium4]

Re: Thermaltake TR2-500 Primary cap bad?

I wouldn't use CapXon caps as primaries in a PSU with PFC

[dmill89]

Re: Thermaltake TR2-500 Primary cap bad?

It could be an underlying issue with the psu but those caps are in a bad location between the primary heatsink and PPFC coil. CapXons are not very durable so it wouldn't be unreasonable for them to have failed again after 5mos. especially if it was heavily loaded and/or poorly cooled. High quality japanese caps could posibly solve the issue.

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

It IS a CapXon. They can fail with no apparent cause...

I wish you were right but I think it's the power supply, not the cap.

Same brand, series and uF-V caps are running in Jou Jye power supplies without a problem for years.

[tom66]

Re: Thermaltake TR2-500 Primary cap bad?

It IS a CapXon. They can fail with no apparent cause...

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

Impossible... My friend called me complaining that his computer would not start. I went there only to find that the psu acted weirdly and when I opened it I had a deja-vu. One of the 2 primary caps bulged again and drained to the point that it measures completely open at the ESR micro meter...

This is very strange, primary caps rarely fail, especially without APFC. All I can think is that something in the power supply makes that primary capacitor bulge.

Sorry, didn't take pics of it yet.

[tom66]

Re: Thermaltake TR2-500 Primary cap bad?

I had a similar PSU (I think 480W, I gave it to my friend). It was even worse, because there's a secondary board crammed with an active PFC stage. Almost no space in it for airflow.

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

Here it is, powering again my friend's PC. Thank you for your help

[dmill89]

Re: Thermaltake TR2-500 Primary cap bad?

So long as the blades are not obstructed and it spins freely you should be ok. I have a TR2-550w (not currently in a computer, kept as a spare), it has Rubycons on the primary but JunFu (rebranded Fuhjyyu) on the secondary. I'd probably rather have it all Teapo like the one you have since Teapos tend to be more reliable than JunFus, of course 100% Japanese Caps would be even better. What is it with CWT, so many of their PSUs are good designs but are let down by the crap caps they use.

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

I have recapped the power supply and it is now working, but.. the plastic holder of the fan is touching the top of the caps.. I managed to close the case and didn't tighten the screws too much... I hope it's ok.

Some photos attached

[mariushm]

Re: Thermaltake TR2-500 Primary cap bad?

Yes, you can replace them with 1000uF, won't be any problems.

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

Can I replace the Teapo primary caps with Capxon? Those caps are really expensive and I thought that the primary caps don't fail often...

Going up from 820uF to 1000uF, will it hurt?

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

Just measured the Teapo 820uF 200V Primary caps:


non bulging: esr: 0.05 capacity: 812uF

bulging: esr: 0.64 capacity: 772uF

[goodpsusearch]

Re: Thermaltake TR2-500 Primary cap bad?

They used 85C caps in a psu

2x 47uF Teapo SK 85C