Glossary of Electric Utility Industry Terms
L – The abbreviation for inductance.
Lateral – A distribution line that branches out from the main distribution line.
Lightning Arrestor – A device used to divert lightning from an electrical system into the earth, minimizing damage to the system. (EUSO, IESO)
Load – Anything that will draw current from a source. Load can be measured in Amps, Watts or Volt-Amperes.
Load Break Elbow – A 90-degree connector used in pad mounted transformers. Load break elbows are designed to be pulled off with a hot stick with full-load current flowing. (CAEDS, EDS, IESO)
Load Interrupter – A switching device used to disconnect equipment at full load. It will not interrupt fault current as a circuit breaker or circuit switcher can. (EUSO, IESO)
Line Jack – (Most areas of North America call a line jack a cutout.) A fused disconnect switch used in distribution that swings open when the fuse link blows, or when a line crew worker pulls it open. Line jack is a regional term used in the Southeast U.S. (EUSO –photo, EDS-photo, CAEDS-photo, IESO)
Load Shedding – A procedure in which customers are disconnected from the utility system. (EUSO, System operator training)
Locked Rotor Amps – The amount of current that would flow if a motor shaft was welded to the housing (so that the shaft cannot turn…locked in place) and the motor then energized. On a practical level, this is the amount of current that will flow as a motor is started under full mechanical load. (CAEDS, IESO)
Locked Rotor Current - The amount of current, measured in amps, that would flow if a motor shaft was welded to the housing (so that the shaft cannot turn…locked in place) and the motor then energized. On a practical level, this is the amount of current that will flow as a motor is started under full mechanical load. (CAEDS, IESO)
Low Side – The low-voltage side of a transformer. (EUSO, CAEDS, EDS, IESO)
LRA – See Locked Rotor Amps.
LTC – An acronym for Load Tap Changer. A load tap changer is a device that will change a transformer’s turns ratio, and therefore the output voltage, without de-energizing the load being served. (EUSO-photo, CAEDS, EDS, IESO, System operator classes)