MCQ
When the current through the electromagnet of a relay reaches a particular value:
- AIt breaks the circuit.
- BIt open the circuit by pulling in an iron contact.
- CIt closes the circuit by pulling in an iron contact.
- DBoth A or C.
✓
Answer
- Both A or C.
Explanation:
They are ways of switching using a low current to use an electromagnet to close or open a spring steel contact.They are often used to isolate a user from a high voltage that needs to be switched, using low current, low voltage to operate the relay, rather than having a user come in direct proximity to the higher voltage that needs to be switched.When the current through the electromagnet of a relay reaches a particular value it either breaks the circuit by repllening or closes the circuit by pulling in an iron contact.
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