Automatic Night Lamp Circuit
Automatic Night Lamp Circuit
It
is very convenient to light a lamp in our absense in the eving when it
gets dark. This automatic night lamp circuit can be used to light
staircase light, porch light etc automatically using domestic
powersupply. It is very in expensive in construction and we dont have to
employ or depend anybody to put on the lights when we are out of
station. We can connect a CFL in place of filament lamp by making
necessary alterations to the circuit.
An SCR and LDR together plays the role of automation in this circuit. In figure, the resistance of LDR is low during daytime and high during night. So the required trigger pulse is developed across the SCR when it becomes dark and it is applied acrosss the gate cathod terminals and SCR is triggered and the circuit is closed.