[SOLVED] Help me replace broken varasitor

tvr10241x

I feed 220V to the power supply board of computer, then one person switch from 220V source to 110V source, the capacitor named TVR10241X is broken
Here is the parameters of that capacitor
Zero Power Varistor Voltage 240V
Max. Allowable Voltage AC(RMS) is 150V and DC is 200V
Max. Clamping Voltage 395V, 25A
Max. Energy 35J
Max Peak Current (8/20) 1 time is 2500A, 2 time is 1300A
Rated Power 0.4W
Reference Capacitance @ 1KHZ (pf) 500pf
Could you tell me why it is broken and at the moment I can find the same kind of that capacitor, could you recommend me some type of it ?
Thanks so much !!!

broken capacitor

This is not a capacitor, it is a varistor that offers protection from high voltage spikes.

If you ommit it the power supply will work fine but no protection from voltage spikes would exist.

You can replace it with a new one provided it is for the same voltage levels that it triggers. This AC and DC voltage ratings are the important parts and then the energy capacity. Energy cap. is not a major issue in Computer PSUs since the usually use a small varistor there. So find one with the same voltage ratings and about the same physical size, it should work fine.

broken pc capacitor dangerous?

So I can replace that varistor with a copper line temporarily ? Is that okey ?
Thanks !!!

reolacing broken capacitators

No, not a copper line because you will create a short. Just leave it open. Simply remove it untill you find a replacement.
The circuit will work without it.

capacitor broken in psu

Varistor is variable resistor, could I replace it with a resistor has the same value to the resistance value of varistor ?
Thanks !!!

how to tell capacitor broken

you must get an old psu and harvest its guts to gain a replacement
it is dangerous to use other than the right part my friend to get it to work
also the bridge rectifer in the psu will be gone
it is common for this to go if the varister is also gone
i think also you will find the switching fet's / transistors
that drive the usualy yellow transformer with 350 v waveform

are also gone

you have this flow in switched mode computer psu>>

mains>> filter >> varistor{current limit{soft start}}>> bridge makes 350vdc>>switching to 700v squared wave 350 0 350 >>
makes >>3.3v switches other rails on computer choice
>> diodes>> 5v {standby rails for memory}>> 12v etc low tension

so as you see its best to check the two fets usualy mounted on a heatsink
and sometimes has another two pin device this is a diode half bridge..for the 5v rail usualy and can be ignored


i would here
replace the varistor/ bridge rectifer /switching fets and there bias
also all small value capacitors like 1uf@50v around it with good quality 105deg caps

infact all the caps
AND !!!! if the psu is over 3years
then also the main 350/ 400v resoviour capacitor
as they get tired after a couple of years and lead to further problems with current avalibility

so replace a few bits... with new / salvaged stuff{get a capacitance tester}

varistor tvr10241x

"infact all the caps"
uhm ... what its mean :|

how to check a broken capacitor

Exactly it is an MOV (metal oxide varistor), this terminology is more popular on the internet and literatures.

You can search on internet for your idea about this part and possible replacement, and then check up with your local electronic part vendor for the closet replacement.