Amprobe PRM-6 Phase Sequence and Motor Rotation Tester Handheld allows the user to determine the correct motor rotation and wiring phase sequence in installation or maintenance. Incorrect wiring can cause the motor to spin a direction it is not designed to, potentially damaging the motor or other related equipment. The Amprobe PRM-6 features advanced non-contact measuring on live motors , 3-phase to phase voltage up to 700V, asynchronous or synchronous motor rotation direction, and more.