Performing basic maintenance on a harmonic filter not only extends its lifespan but also helps prevent downtime and costly repairs. In this article, we’ll delve into the essential steps involved in maintaining a harmonic filter to keep your electrical system running smoothly.

Visual Inspection:

  • Start by visually inspecting the harmonic filter for any signs of damage, such as cracks, discoloration, or loose components.
  • Check the wiring connections to ensure they are tight and secure.
  • Inspect the filter enclosure for dust buildup or debris that could obstruct airflow and reduce cooling efficiency.


  • Dust and debris can accumulate on the surface of the harmonic filter over time, compromising its performance.
  • Use a soft brush or compressed air to gently remove dust and dirt from the filter components, including capacitors, reactors, and cooling fins.
  • Avoid using harsh chemicals or abrasive materials that could damage the filter’s components.

*Always follow the manufacturer’s guidelines when cleaning equipment.

Periodic hardware upgrades (AHF only):

  • Change fan filters
  • Change fans (typically every 3 years)
  • Change fuses (typically every 3 years)

Integrating with Power Monitoring System:

  • Integrating your harmonic filters into a power monitoring system like PME will allow you to monitor and measure for efficiency and reliability.
  • PME can analyse things like the temperature of the harmonic filter components which could indicate a malfunctioning component or poor airflow within the enclosure.

Functional Testing with PME:

  • Test the performance of the harmonic filter by monitoring harmonic levels and power quality parameters before and after the filter.
  • Use power quality meters connected with PME you can measure harmonic distortion levels and verify that the filter is effectively reducing harmonics.
  • Create alerts and alarms to monitor the voltage and current waveforms to ensure they remain within acceptable limits and do not exhibit any abnormalities.

Documentation with PME:

  • PME can become your master document library keeping detailed records of all maintenance activities performed on the harmonic filter, including inspection results, test measurements, and any corrective actions taken.
  • Note any abnormalities or issues observed during the maintenance process and document the steps taken to address them.
  • Maintain a maintenance schedule to ensure regular inspections and testing of the harmonic filter are conducted at appropriate intervals.

Performing basic maintenance on a harmonic filter is essential for ensuring the reliable operation of electrical systems and preventing costly downtime. If you would like assistance scheduling regular maintenance intervals and keeping detailed records of all maintenance activities give our power quality team a call today.

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