Reworking this cap checker and I need to replace a 8 MFD @525v. Seems the highest voltage I can find is 450v. Anybody have a source for a higher working voltage cap? TIA.<P>------------------<BR>Jim

Hi Jim<P> AES, <A HREF="http://www.tubesandmore.com" TARGET=_blank>www.tubesandmore.com</A> has 500 volt electrolytic caps. You could series 2 - 16 mfd caps?<P>------------------<BR>Norm

Even 2 22uf in series would be ok. If you use 2 450v units you would probably not even need balancing resistors.<P>------------------<BR>

Hi Jim,<BR>Mouser has 10uf, 600v caps in stock, but they are not cheap at $11.63 each: <A HREF="http://www.mouser.com/index.cfm?handler=displayproduct&lstdispproductid=265504&e_categoryid=500&e_pcodeid=75002" TARGET=_blank>http://www.mouser.com/index.cfm?handler=displayproduct&lstdispp roductid=265504&e_categoryid=500&e_pcodeid=75002</A> <P>------------------<BR>Carl

<P>This would be a much better solution than wiring two caps in series. Definitely the "right" way to do it IMHO.<P>------------------<BR>73 de Leigh W3NLB | | Leigh@AtwaterKent.Info<BR><A HREF="http://www.AtwaterKent.info" TARGET=_blank>http://www.AtwaterKent.info</A> | | <A HREF="http://www.Synchrophase.info" TARGET=_blank>http://www.Synchrophase.info</A>

Maybe I'm misunderstanding something here. I always thought that unlike resistors, no matter how you wired them together, the max voltage the caps could stand would not change, ie. 2 450V caps = 1 450V cap. Unlike 2 paralleled resistors where 2 half watt = 1 one watt. Or is that 525V cap rating not all that critical here. I have a 950B and used a 600V cap.<P>------------------<BR>

Hi Kent,<P>No, voltage ratings of capacitors in series are additive. So a pair of caps rated 1000 volts wired in series would yield a 2000 volt rating. This only works for identical capacitors.<P>The idea being that the insulation in the capacitor is not perfect, so there is some leakage current flowing. Thus, you actually have two resistors in series, and the voltage divides equally across the resistors. Thus, the voltage across each individual capacitor is still within ratings.<P>Two caps in parallel would have a voltage rating equal to the lower voltage cap, i.e. a 100-volt in parallel with a 250-volt would be rated 100 volts.<P>However, as mentioned in my previous post, the "proper" replacement is a single cap rated at least 525 volts. The 600 volt cap would be fine.<P>------------------<BR>73 de Leigh W3NLB | | Leigh@AtwaterKent.Info<BR><A HREF="http://www.AtwaterKent.info" TARGET=_blank>http://www.AtwaterKent.info</A> | | <A HREF="http://www.Synchrophase.info" TARGET=_blank>http://www.Synchrophase.info</A>

Thanks for all the replies. Think I'll go the single cap route.<P>------------------<BR>Jim

Yes, but modern mylars are likely to be pretty close. Ideally you'd measure them on another cap meter.<P>Check the voltage pot: they're prone to burnout at the bottom end, when some careless user discharges a large electrolytic into it by turning it down to zero too fast.<BR>------------------<BR>