On Nov 17, 11:50 am, Mike wrote:
I have a light that refuses to go on.

The light switch (wall type) is connected to a relay. Now the relay won't
"click". It used to work a couple of days ago. The relay has operating voltage of
24V which switches a 240V line (lights).

I would like to test (using a voltmeter) where I'm having problems. How do I
measure if 24V is going through the coil/magnet.

The relay box looks like this (wires go to points A,B,C,D):

A 24V b
-------------
| |
| |
| |
| |
| |
C------------D
240V

When the switch is off volmeter shows 240V between C and D

When the switch is on volmeter shows 0V between C and D

How do I measure voltage in A and B?

Um, the first question, everyone didn't ask. Is there
only "one" light or does this circuit feed several lights?
If there is more than one light on the circuit and only
one is dead, the 240 volt reading between C and D is
through the filaments or ballasts of the other lights.
If that's the case, look at the socket or connections
for the dead light.

[8~{} Uncle Monster