Caps and ESR

[Larrob19]

Hello,

I would like some advice on ESR. I have 3 Capacitors that are 68uf 500v. The 3 are showing about 62uf and 0.66 ohm. Does the ESR look OK?

[CapLeaker]

They seem to be within tolerance. However high voltage capacitors have higher ESR from the get go than low voltage caps and actually need to be checked with a big ESR meter that ca do a leakage test. These little ESR testers do not charge the capacitors up to 500v. Just food for thought. This cap may be ok for the TV”s, but for big things that need a lot of power, leakage test it is hands down.

[Larrob19]

Thanks for the info CapLeaker. The reason I asked was because it's a Samsung TV Power Board and it keeps burning 2 Power Mosfets and the main fuse. It never blows the Blue Caps next to the Mosfets or the Diode also. I connected a 100 watt light bulb to it and when plugged it flashes 1 to 2 times per second. I have looked for a schematic for this board BN44-00874C but no such luck. This has me stumped.

[CapLeaker]

Look at the gate drive including the PWM for start. Maybe make a new thread in the TV section about your problem TV, take some straight shot, high resolution picture pics and upload via attachment function and explain exactly what had happened and what you did. There are some real capable folks here on badcaps.

[Larrob19]

I will try that. Thanks CapLeaker.