When a crowbar is used with a power supply the supply needs to have a fuse or

When a crowbar is used with a power supply the supply

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113.)When a crowbar is used with a power supply, the supply needs to have a fuse or114.) a. Adequate trigger currentb. Holding current115.)c. Filteringd. Current limiting116.)The diac is a117.)a. Transistorb. Unidirectional device118.)c. Three-layer deviced. Bidirectional device119.)The triac is equivalent to120.)a. A four-layer diodeb. Two diacs in parallel121.)c. A thyristor with a gate leadd. Two SCRs in parallel122.)The unijunction transistor acts as a123.)a. Four-layer diodeb. Diac124.)c. Triacd. Latch125.)Any thyristor can be turned on with126.)a. Breakoverb. Forward-bias triggering127.)c. Low-current drop-outd. Reverse-bias triggering128.)A Schockley diode is the same as129.)a. A four-layer diodeb. An SCR130.)c. A diacd. A triac 131.)The trigger voltage of an SCR is closest to132.) 134.)Any thyristor can be turned of with135.) 140.)A four-layer diode is sometimes called a141.)
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153.) b. The ohmmeter cannot supply more than 0.7 V 154.) c. The ohmmeter must supply the SCR’s reverse breakover 155.) voltage 156.) d. The ohmmeter must supply the SCR’s holding current 157.) The maximum firing angle with a single RC phase control circuit is 158.) a. 45° b. 90° c. 180° d. 360° 159.) A triac is generally considered most sensitive in 160.) a. Quadrant I b. Quadrant II 161.) c. Quadrant III d. Quadrant IV 162.) A PUT is considered programmable by using 163.) a. External gate resistors 164.) b. Applying preset cathode voltage levels 165.) c. An external capacitor 166.) d. Doped pn junctions 167.) 168.) Prepared By: Reviewed By: Approved By: 169.) 170.) Engr. G. Lagos Engr. Y.
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  • Summer '15
  • Engr. Lagos
  • It, SCR, four-layer diode, a. diac b., diac b. triac

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