Emergency lights turn off electricity and unexpected power outages, how emergency principle?
The emergency lights should also have a manual switch, in series with the relay normally closed contact, turn off the manual switch, emergency lights will be closed.
The relay contacts are normally closed contacts and normally open contacts. The normally closed contacts are disconnected when the circuit is energized, and the normally open contacts are closed when the circuit is energized.
the relay coil by the electric power supply, electric power, said contacts are open, when the city electricity power, no electrical relay coil, relay contacts the closed front said, launched the emergency light power supply itself.
The emergency lamp power from the normally closed contact of a relay is controlled, the contacts are open in the relay coil is energized,
