Is Your Electrical Equipment Safe?

Is Your Electrical Equipment Safe?

electrical unit

The only way to be certain is to have a trained technician perform a PMI on your electrical equipment. PMI is an acronym for Preventive Maintenance and Inspection. The term is used generally in all manner of the industry to describe the activity of performing regular required maintenance and inspection of equipment and/or systems. The purpose is to keep things running at top performance and to detect abnormal conditions or wear so that they can be corrected before an unpredicted failure occurs. Electrical PMI focuses on electrical systems and equipment. These systems have unique characteristics and require specialized maintenance and inspections by technicians trained in what to look for.

The specific areas addressed are:


This step commonly skipped or done halfheartedly, is one of the most important in keeping the system up and running. The purpose of cleaning is to remove accumulations of contaminants (dirt, dust, etc.) from insulators, vents, circuit breakers, and switch surfaces so they don’t cause catastrophic failure. These surfaces are supposed to separate (insulate) the various electrical pathways within the equipment so that they do not interact. Contaminants can create a connection between the electrical pathways, and when that happens, the damage is usually extensive. Cleaning is no longer an option - complete replacement is.

Visual Inspection

Some potential electrical problems can be avoided by simply visually inspecting the equipment and systems. By looking for anything out of the ordinary, like discoloration of conductors and components, corrosion, pinched or otherwise damaged wires and cables, missing covers, supports, brackets, etc. Essentially, we are looking for anything out of the ordinary which could cause a problem.


Bolts and nuts can loosen over time, and loose connections cause excessive heating which can destroy electrical equipment. As a part of any PMI, each bolted connection is checked for proper torque and brought up to spec as needed.

After the cleaning, visual inspection, and torque, there are several other actions including insulation testing, thermal imaging (to locate areas of abnormal heating), circuit breaker resistance and trip testing, and ground fault testing. To learn more about these, visit our Electrical Info Center at

Preventive Maintenance & Inspection of your electrical equipment should be done at least annually to keep your equipment in good condition and prevent any unforeseen problems. Contact us online or call us at 323-255-6563 or

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