This part of IEC 1270 applies to capacitors for microwave ovens operating at rated a.c. voltages of up to 3 000 V and a superimposed d.c. voltage of up to 0,8• 1,E times the value of rated a.c. voltage. This standard relates specifically to capacitors with a metal case and an upper rated maximum temperature of up to 100 °C, non-self-healing, with metal foil electrodes and dielectrics of paper and/or plastic, impregnated with a suitable oil.