1 Crore+ students have signed up on EduRev. Have you? Download the App |
In a silicon controlled rectifier (SCR) in its forward cutoff region injecting a current into the cathode gate terminal can
By controlling the point in each half cycle when the SCR turns on, the SCR-based control circuit achieves
Assertion (A) : The operation of an SCR can be explained in a very simple way by considering it in terms of two transistors.
Reason (R) : in the two transistor analogy of the SCR, the SCR can be considered as an npn and a pnp transistor, where the collector of one transistor is attached to the emitter of the other and vice-versa.
After firing an SCR, the gate pulse is removed. The current in the SCR will
Assertion (A) : If the one-state anode current drops below a minimum level, designated as the holding current IH, the thyristor reverts to the forward blocking state.
Reason (R) : The loop gain of the equivalent pnp-npn transistors fall below unity and the regenerative hold-on action ceases.
The main reason for connecting a pulse transformer at the output stage of a thyristor triggering circuit is to
23 docs|285 tests
|
23 docs|285 tests
|