Partial Discharge Service
What is Partial Discharge?
Partial discharges (PD) are small electrical sparks that occur within the insulation of medium and high voltage electrical assets. Each discrete partial discharge is the result of an electrical breakdown of an air pocket within the insulation. These discharges erode insulation and eventually result in insulation failure.
According to the National Fire Protection Association (NFPA 70B), the leading cause of electrical failures is insulation breakdown. The National Electrical Code (NEC) states that these partial discharges are the first indication of insulation deterioration. Research indicates that cables, switchgear, and transformers suffer the greatest losses from insulation.
What we do?
We collect data through Partial Discharge Testing and Monitoring solutions which can provide critical information on the quality of insulation and its impact on overall equipment health. Because partial discharge activity is often present well in advance of insulation failure, asset managers can monitor it over time and make informed strategic decisions regarding the repair or replacement of the equipment.
These predictive diagnostics help companies to prioritize capital and MRO investments before an unexpected outage occurs. Partial Discharge Testing results can help predict future performance and reliability of critical assets, including:
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Cables, splices, and termination
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Power transformers and bushings
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Switchgear
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Motors and generators
Failures are not limited to service-aged equipment. Partial Discharge testing on newly installed equipment builds reliability right from start. Partial Discharge Testing can:
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Verify original manufacturers test data and identify damaged insulation that occurred from improper installation, poor design, and/or poor workmanship during or after installation.
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Identify premature failures and capture baseline data to trend asset health over the asset’s life cycle to ensure maximum return on investment.
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.
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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.
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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.
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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.
