Capacitor question

I'm rebuilding a small engine coil tester for a neighbor. It originally used a 1uF and 2uF 600V, oil filled NON POLARIZED electrolytic capacitor(s).. Can 630V polypropylene caps be used, or should I look for motor-run caps? Thanks.

by Mr.Z
October 27, 2021

A bi-polar (or non-polarized) capacitor is equivalent to series connection of two capacitors, but in half the occupied volume of two capacitors, achieved through special construction.

First time that I heard of oil being used in capacitor, but technically, if the space (volume and weight) allows it, you can use a film cap as replacement to electrolyte. The possible advantages of electrolytes being their smaller size, weight, greater availability, and price. Not their electrical behavior. When welding a film cap, be sure to not over-heat its pins, excessive heat may propagate and melt part of the film material. If hyper-critical, someone can weld a socket and then, insert the cap mechanically into the already welded socket.

by vanderghast
October 28, 2021

Vandergast. Either you're showing your age or I'm showing mine. For many years for big high voltage capacitors oil was the only way to go. In the early days of electronics it was still used for high voltage but was eventually replaced by the plastic film we see now.

by Foxx
October 31, 2021
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