PSU fet sink hot when off

[willawake]

i have noticed that my chieftec psu hpc-360-202 has the fet heatsink next to the primary caps being really hot when the computer is plugged in but off.

how hot is it? well you couldnt touch it for too long.

is that something i should worry about?

[PeteS in CA]

Re: PSU fet sink hot when off

How long has the P/S been off? If the +5V Stby regulator (or switch device) is on that heatsink, how long has the power cord been unplugged. From your description, it sounds like the heatsink temp is about 55C-60C, so if it hasn't been off very long, that might be normal. Or your fan-speed regulator may not be responding to temperature and running the fan too slow.

[willawake]

Re: PSU fet sink hot when off

hmm i didnt think of that . i will check in the morning if i made that mistake. would be nice to have a circuit to run the fans for 15mins after shutdown like the cars.

fan-reg is bypassed since this afternoon, it is getting 12v only now with new powerful pelko fan. exhaust is now cool but unfortunately i have found source for delta EHE fans so i think i will get a new cheapo case and run 2x120mm EHE and 1x80mm EHE for the psu.

i think my music is in excess of 65db so we are probably ok for the gaming rig

[PeteS in CA]

Re: PSU fet sink hot when off

Any helpful info here, willa?

[larrymoencurly]

Re: PSU fet sink hot when off

Did you measure the DC voltage between the heatsink and ground before touching it? Because some of those heatsinks have over 160VDC on them, as I've found with Delta, Antec SmartPower, Enermax, and Leadman/Powmax/Raidmax.

I don't know how much heat the power transistor of the standby regulator puts out, but I doubt that it's enough to make the big heatsink very hot because otherwise there wouldn't be so many of those transistors separate from that heatsink with just a small piece of aluminum attached to them.

[dood]

Re: PSU fet sink hot when off

https://www.badcaps.net/forum/showthread.php?t=1306

[willawake]

Re: PSU fet sink hot when off

wb dood thanks for the link.

ok the heatsink is indeed hot even after the comp was left off overnight. actually i can only find medical thermometers in the house at the moment. the digital one informs me that my psu has a fever . the analog read its maximum 42oC. so i guess it is like pete said

anyway like Rainbow said on the link and pete said here i guess it is normal. it is just suprising.

The heatsink measured to ground 156vdc like larry said.

[kc8adu]

Re: PSU fet sink hot when off

The heatsink measured to ground 156vdc like larry said.

now you know what to touch for your daily electroshock therapy

[willawake]

Re: PSU fet sink hot when off

dammit how did you find out about that?

[Per Hansson]

Re: PSU fet sink hot when off

Maybe like this? :P

https://www.badcaps.net/forum/showpo...94&postcount=4

[willawake]

Re: PSU fet sink hot when off

no i wanted to know how he found out about my daily electroshock therapy

[kc8adu]

Re: PSU fet sink hot when off

we have ways of finding out....

[arneson]

Re: PSU fet sink hot when off

I like the IGEA Electrosage machine "as seen on TV".
Just don't hook up to your balls.