Plastic capacitors. A comparative investigation of the quality and stability of 31 manufactures and types, including 5 different dielectrics

Thirty-one types of capacitors distributed over 14 different manufactures and representing the various existing kinds of dielectrics, including both the metallized and foiled types were tested. An AC and DC-life test at max. temperature were included as a part of the climatic environment exposures to examine a possible difference in the stability of the capacitors in the two different kinds of life tests. The test showed that several of the capacitors manage an AC-life test better than a DC-life test. A pulse test of the capacitors with a dV/dt of a max. of 700 V/microsec showed a great dispersion among and within the various manufactures and as expected the foiled types proved in general to manage better than the metallized types.