The PDetector is the ideal device for Online Partial Discharge (OLPD) testing of medium and high voltage electrical equipment. Online PD testing is a method of inspecting the insulation of electric power systems while electrical equipment remains energized and in service. The PDetector employs all 5 types of sensor technology for online PD detection: TEV, UHF, HFCT, AE, and Ultrasonic. Information from multiple sensors gives the PDetector the versatility needed to detect all types of PD in all types of substation apparatus. Furthermore, the exact type (mechanism) of PD activity can be determined instantly using on-screen Phase Resolved Partial Discharge (PRPD) & Phase Resolved Pulse Sequence (PRPS).