Clarification WV??

Hello i need a bit of clarification, i have several capacitors with markings of 200WV @ 1000uF, am i correct in assuming (WV) this means Watt-Volts, i understand the 1000 micro Farad, and i can charge them up to 250V, this is causing some confusion

Thank you for any replies.

WV= working voltage...In other words.. do not exceed this voltage.

Oh, thanks, i have been charging up to 250V, bit of a mistake, but they seem to work fine, i will stop charging them to 250v as this is probably causing undue stress on the dielectric, i am quite surprised that the dielectric didn't give up or break down??

thanks for the reply

Yeah, it is not wise to exceed the WV on electrolytic capacitors. Exceeding it makes the dielectric become conductive and the charging current then heats it up rapidly. Old capacitors could explode if the rated voltage was exceeded, modern ones of any size should have a vent (a K or X shape cut into the top) where the hot liquid can excape in a failure.

Yes, I'm amazed they haven't already blown? - generally voltage ratings are pretty accurate, a few percent over and they die big time!.

These are pretty old, i swiped them from an old photocopier, they have no vents and until i measured the voltage they were charged at today i had no idea that i was overcharging them.

my mate has blown a few up before though!

Electrolytic caps usually have a working voltage rating, and a surge voltage rating. Surge voltage ratings are usually 10-20% above the working voltage. In any case, electrolytics are pretty tame. I'd guess that the electrolytics will lose capacity, show an increase in impedance and an increase in self-discharge. After all the gradual damage happens, you'll see all the fun results of boiling electolyte in a can. In comparison, the poster child for picky capacitors are the tantalum variety: need a 50% voltage *derating* versus their "WV" rating and when they die, they explode within seconds.