Terms beginning A - G

The SPDC Glossary is a compilation of the terms extracted from SPDC 2011 active Standards, Guides and Recommended Practices. The last line of each term definition references the document number the term came from. There are 135 terms with multiple entries as the term has occurred in several documents. There are over 400 unique terms in the Glossary. The Glossary terms are alphabetically arranged, with a page for each letter. If the Glossary is directly accessed, a randomly selected term and definition is given at the top of the page. Once a particular letter page is selected, the random term disappears.

Clicking on a term on this page will take you to that Glossary page for that term definition. The following terms are defined in the Glossary:

A – AC standby power (Varistor), anode, anti-parallel (connection), arc current, arc voltage, arrester, arrester discharge current, arrester discharge voltage, arrester disconnector, arrester duty cycle rating, arrester unit, arrester, deadfront type, arrester, distribution, heavy duty class, arrester, distribution, light duty class, arrester, distribution, normal duty class, arrester, liquid-immersed type, arrester, riser pole type, atmospheric correction factor, avalanche breakdown diode (ABD)

B – back filter, back flashover, back flashover (lightning), back-up air gap devices, balanced voltage limiting, basic lightning impulse insulation level (BIL), basic switching impulse insulation level (BSL), bidirectional thyristor, blocking, blocking voltage, breakdown, breakdown (clamping) region, breakdown current, breakdown region, breakdown voltage, breakdown voltage, ac, breakdown voltage, dc, breakover current, breakover point, breakover voltage

C – capacitance, capacitance (Varistor), cascade coordination, cathode, certification tests, characteristic, clamping (suppression) voltage, clamping factor (CF), clamping voltage, class of grounding, classification of arresters, classifying current, coefficient of grounding (COG), combination wave (1.2/50, 8/20), common-mode, component surge-protective device - voltage limiting type, component surge-protective device - voltage switching type, component surge-protective device (component SPD), conformance tests, continuous operating current, conventional basic lightning impulse insulation level (BIL), conventional basic switching impulse insulation level (BSL), conventional BSL (basic switching impulse insulation level), conventional withstand voltage, coordination of insulation, counterpoise, coupling factor, coupling wire, cracking, crest (peak) value (of a wave, surge, or impulse), crest value (peak value), crest value(of an impulse), critical flashover voltage (CFO), critical rate of rise of off-state voltage, critical rate of rise of on-state current, current chopping (rotating electric machinery), current turnoff time, current zero (rotating electric machinery)

D – damage, dc holdover, dc holdover voltage, DC standby current (Varistor), deadfront type arrester, deflector, degradation, design tests, device failure, diode, discharge counter, discharge current, discharge indicator, discharge voltage, discharge voltage-current characteristic, discharge withstand current, disruptive discharge, distribution arrester, duty cycle test, duty-cycle voltage rating, dynamic impedance (Varistor)

E – effectively grounded system, electrical environment, electrical unit, energy deposition, external insulation

F – fail-safe, failure, failure mode, fault, fault current, ferroresonance, flashover, follow current, follow current (power), forced current zero (rotating electric machinery), forward conducting region, forward current, forward direction, forward voltage, forward/reverse conducting quadrant, forward-conducting diode thyristor surge protection device (SPD), forward-conducting triode thyristor surge protection device (SPD), front-of-wave impulse sparkover voltage, front-of-wave lightning impulse voltage shape

G – gapless, gas-tube surge arrester (gas-tube surge-protective device component), gate, gate reverse current, adjacent terminal open, gate reverse current, forward conducting state, gate reverse current, main terminals short-circuited, gate reverse current, on-state, gate switching charge, gate-to-adjacent terminal breakover voltage, gate-to-adjacent terminal peak off-state voltage, glow current, glow voltage, glow-to-arc transition current, grading or control ring, ground insulation (rotating electric machinery), ground potential rise (GPR), ground terminal, ground-fault factor