Case Studies

A high frequency TDR test was performed on a General Electric 150 HP 1770 RPM 460 Volt motor. The test indicated that there was a large amount of reactive faults in the motor. The motor was disconnected from the line and the motor and lines were tested separately. It was determined that the problem was in the lines and not the motor. Upon further inspection of the lines it was found that the contractor had damaged the cable jacket when it was pulled.

The chart indicates the amount of reactive faults in the first test and the amount of faults after the cable was replaced. This is another indication of how high frequency testing can find faults in cables as well as motors.

Otis Elevator Case Study

Otis Type 77 Eevator Field Study

New York Building Field Study