Field Testing Services

PMDT offers three levels of testing services both domestically in the US and globally. With the best quality products, complete PD solutions, rich on-site testing experience, experienced partial discharge experts and field engineers, PMDT also provides PDExpert Services -- professional on-site partial discharge detection and location services to help the customers find the potential risks, evaluate the operating status of the electrical assets, and deliver complete and final problem solutions.

  • Level 1 OLPD Detection Service: This is a routine inspection for any PD signals on your typical substation equipment and power assets. Once data is collected and analyzed, a report will be provided with any abnormalities given and if PD is found, maintenance suggestions will also be provided.

  • Level 2 OLPD Diagnostic and Location Service: If PD is already a known issue, we offer a location service where our technicians will utilize our accurate location solutions to locate the  PD signal source, whether it is internal or external of the power asset. 

  • Level 3 OLPD Expert Location Service: We utilize our exclusive PDExpert with acoustic-electric combination PD source localization system , which helps locate the PD source down to the centimeter. 

We obtain the signal characteristics detected and analyze the resulting signals, evaluate the condition, and provide a detailed test report as well as maintenance suggestions for the detected high voltage electrical equipment to the customer. 

Benefits of Online PD Testing:

  • Evaluate the condition of insulation in advance of a failure

  • Evaluate the power asset under normal operating levels and conditions, providing an accurate analysis of the asset

  • Detect and locate PD within power assets using non-invasive sensors, causing little to no disruptions to operations

  • Analysis of PD signals can provide PD type and strength

Field Fault Location Services


PMDT offers services to diagnose and locate PD signals within your power asset precisely and accurately. Using our PDiagnostic Series and PDExpert solutions, along with multiple location techniques implemented with the devices, our field engineers can locate the PD source down to the centimeter.  

Global Testing Experiences

PMDT’s unique experiences consist of over 25 years of R&D combined with many years of field work: testing PD and Infrared for over 200,000 various power assets in thousands of substations globally for a variety of electric utilities, industrial end users, and power equipment manufacturers. PMDT has the expertise needed to provide the best Condition-Based Maintenance Programs for your power assets.