On-line Partial Discharge FAQ

Have some questions about Partial Discharge? Why not check the frequently asked questions (FAQ) below? You might find answers to most of your questions.

If you cannot find answers to your questions, please do not hesitate to email us sales@ipec.co.uk

 

IPEC PD Monitoring Systems

  1. Q1. What PD monitoring systems do IPEC offer?

    IPEC PD Monitoring Systems:

    • PD Alarm: 4 channel PD monitoring system for AIS (Air-insulated switchgear)
    • ASM: 4 to 128 channels Short/Long term PD monitoring for cable, AIS, GIS, and dry-type transformer
  2. Q2. Can on-line PD monitoring be used on transformer HV bushing?
    Yes, HV bushing monitoring is possible where the bushing has a bushing tap. In this case, a simple adaptor is used to connect directly to the PD Monitoring system. Normally each bushing would be monitored separately.
  3. Q3. How often should on-line PD monitoring systems be inspected or calibrated when they are in service?

    We normally recommend a full health check which includes calibration every 24 months.

    The monitors have built-in system diagnostics that continually check the PD monitor health and raise an alarm if maintenance is required.

  4. Q4. Can end-user perform reliability analysis with the system? Is it possible to export data?

    The PD data can be analysed in detail using the many graphing tools on the iSM website.

    Data can also be exported in .csv format if required

  5. Q5. How can IPEC’s PD monitoring system pick out PD in a high noise level environment

    IPEC use our DeCIFer™ Algorithm which we designed to distinguish between PD and noise. Our ASM samples signals at 100MSample/sec and 14-bit resolution, which means we will be able to have high-resolution data and be able to see small PD spikes even among large noise. Our DeCIFer™ Algorithm uses Wavelet Analysis to effectively picking out potential PD signals from noise, and then uses PD Knowledge Rules Analysis which is based on IPEC’s experience of over 20 years of PD data analysis. These enable our DeCIFer™ Algorithm to effectively differentiate PD from noise.

  6. Q6. Can IPEC’s PD monitoring system detect cable PD if there are lots of joints on the cable?

    One HFCT on one side of the cable can normally monitor upto 4-5 km of cables (with cable joints in between). If cables are longer, we recommend installing HFCT and monitoring systems at both cable end. Or, if cable earth is accessible at each cable joint (at link box), we can install HFCT and ASM at cable joints for full coverage of cable PD monitoring. This is a common application in EHV networks.