Voltcraft phase rotation tester vc3x series voltcraft vc36 the voltcraft vc36 is a phase rotation tester that is able to check the phase sequence or direction of rotation of motors without a frequency converter in a three phase networkthe meter shows whether all 3 phases are present the measurement is performed by means of the three test leads and the alligator clips which are supplied or contactless directly via the magnetic field of an ac motor in the range of measurement category cat