Power Transient Monitor

The power transient monitor is a specialized electric equipment developed to provide the capability of automatically and unattendedly recording randomly occurring power transients and disturbances in electric power systems. Twelve magnetic data channels record power waveforms and 14 pulse-voltage counters register the occurrence of pulse-voltage transients according to magnitude and duration. The power waveforms are continuously recorded and erased from a rotating magnetic drum. When a transient is sensed, a record signal is provided to a quick-start magnetic tape whereupon pretransient, transient, and post-transient waveforms are transcribed from the drum onto the tape. The time of each recording is also indicated on the tape. The waveform recordings can be viewed on an oscilloscope or reproduced on an oscillograph. Representative transient recordings made with the monitor at six widely separated continental and overseas field installations are presented.