Measurements

Voltage and Current (2)

  • Moving coil meters only respond to d.c. – to measure a.c. the voltage/current is rectified using a bridge rectifier
  • The voltmeter responds to average values of a.c., but are calibrated in r.m.s.  Therefore use on other than a sine wave will lead to errors
  • The response of the meter changes with frequency and typical meters have a range up to 20kHz