Specifies test methods for immunity to ripple at the d.c. input power port of electronic or electrical equipment. Applies to low-voltage d.c. power ports of equipment supplied by external rectifier systems, or batteries that are being charged. Establishes a reproducible and common basis for laboratory testing, of electronic and electrical equipment when subjected to ripple voltages such as those generated by auxiliary service and/or rectifier systems battery charges overlaying on d.c. power supply sources.