PMI is an acronym for Preventive Maintenance Inspection.  The term is used generally in all manner of industry to describe the activity of inspecting equipment an/or systems for abnormal conditions or wear which should be addressed to keep the system up to snuff.   Electrical PMI focuses on electrical systems and apparatus.  These systems have unique characteristics and require specialized inspections by technicians trained in what to look for. The specific areas addressed are: Cleaning 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 breaker 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.  Torque 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.  Thermal Imaging Thermal imaging (sometimes called thermal-scanning or infrared-scanning) locates areas of abnormal heating.  As overheating of electrical equipment is a prime cause of failure it is important to detect and correct early. Over heating is caused by either loose or poor electrical connections or overloads.  By using thermal imaging equipment we can locate potential trouble spots which would not be visible to the naked eye.  There are several other actions that can be done as part of this such as insulation testing, circuit breaker resistance and trip testing and ground fault testing.  To learn more about these, visit our Electrical Info Center. CALL 323.255.6563 or Request Service Online