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: I have a question about caps voltage. I need a capacitor about 2nF and
: I decided to assemble it from smaller caps (
: http://www.wima.com/EN/mkp10.htm ). These Caps have rated voltage e.g.
: 2000 VDC and 700VAC Should I use the AC rating for design?
: I don't need it for TC but for HV HF Arc starter for welding machine. It
: works on the same principle as the TC. HV cap - Spark gap - coil.
: Thank You for reply.
: Hello Michal,
: Your application is very similar to a Tesla Coil since the capacitors will
: also see intermittent high Q "ringing" (oscillatory) HV RF
: voltage and potentially high "tank circuit" currents. The
: capacitors you've selected are low loss and self healing, and are ideal
: for this appplication (and for TC's).
: For long life in RF applications, the total DC voltage rating of the
: string of capacitors should be at least 3 times the faceplate RMS output
: of the HV transformer that provides power to the arc starter. Using a 3X
: derating factor should provide you with sufficient protection from the
: effects of rapid (RF) voltage reversals.
: Good luck and best wishes,