Organization and Operation
- IEEE/IEEE-SA/PES relationship to SPDC
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- Organization and Operation
Meetings & News
- 2017 Fall SPDC Meeting
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- SPDC 2005-10_Fall-Meeting
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- PES 2006-06 Meeting
- SPDC 2006-10_Fall-Meeting
- SPDC 2007-05_Spring-Meeting
- SPDC 2007-10_Fall-Meeting
- SPDC 2008-05_Spring-Meeting
- SPDC 2008-11_Fall-Meeting
- SPDC 2009-05 Spring Meeting
- SPDC 2009-10 Fall Meeing
- SPDC 2010-11_Fall-Meeting
- SPDC 2011-05_Spring-Meeting
- SPDC 2011-10_Fall-Meeting
- SPDC 2012-11 Fall-Meeting
- SPDC 2013-05 Spring Meeting
- YouTube Protection Videos
- New NEMA page
SPDC Terms beginning with U
Terms and definitions extracted from current SPDC published documents
Click one of the capital letters above to advance the page to terms beginning with that letter.
- ultimate mechanical strength-static (UMS-static)
The load at which any part of the surge arrester fails to perform its mechanical function.
- ungrounded (isolated) system
A system, circuit, or apparatus without an intentional connection to ground, except through potential-indicating or measuring devices or other very-high-impedance devices.
- unidirectional thyristor surge protection device (SPD)
A thyristor SPD that has switching characteristics in only quadrant.
NOTE: The main unidirectional thyristor SPDs are the reverse-blocking, reverse conducting and forward conducting thyristor SPDs.
- unit operation
Discharge of a surge through an arrester while the arrester is energized.
- unit operation
A discharge of a surge through an arrester while the arrester is energized.
Malfunction of a system because of electrical disturbances.
- utilization voltage
The root-mean-square (rms) phase-to-phase or phase-to-neutral voltage at the line terminals of utilization equipment.