On Friday, December 20, 2019 at 9:51:25 PM UTC-5, Oumati Asami wrote:
On 20/12/19 22:25, micky wrote:
In alt.home.repair, on Fri, 20 Dec 2019 14:39:41 +0630, Oumati Asami
wrote:

The light in the laundry room stops working after worker had worked on
the ceiling in the next room.

There are two wires coming in to the light (or one in one out). Before I
flip the switch, both wires are not charged as tested by a tester. After
flipping the switch, both are charged. Yet, the light just won't light.

I removed the light and plug it in to a socket, it works.

Question:

1) did the test (both wires not charged and then charged after flipping
the switch) I do make sense?

2) how could the work in the other room affect the light next room? I do

I put a dimmer on the dining room light, got interrrupted in the middle
for a long time, then didn't know why the range hood didn't work. The
wire for the range hood came out of the box with the dining room light
switch. Of course the wall was right between the rooms.

You're using a real volt meter, not a neon light or something? The
lightbulb is not in the socket when you are testing the voltage to it?


I used a neon light tester. The light bulb was in the fixture.

That's why both wires tested hot. Looks like the neutral is disconnected.
With the neutral disconnected, no current flows and both sides of the
load will be at the same potential. Since you say just two wires enter
the light, the only way I can see that explains all that you reported is
this. Power comes to fixture A in the other room that was worked on.
From there, a cable goes to the switch that works fixture B, the one
that doesn't work now. One wire of that cable is
connected to incoming power hot at fixture A location. That wire is
connected to one side of the switch, the other wire connects to the other side
of the switch. Back a fixture A, another cable runs over to fixture
B, the one that won't light now. One wire of that cable connects to
the above wire coming from the switch, the other to the neutral. If
that neutral connection was undone at the fixture A location, it
would explain what you are seeing.


The light
worked when both the fixture and the light bulb were removed and
connected to another circuit.

see that there are three wires in the switch box, none of them neutral
or ground. They are all live wires. Two on one side of the switch, one
on the other side. The two are charged, the other is only charged after
the switch is flipped.

Where do the two wires go? If what I say above is right, one wire from
the side with two wires and the wire from the other side of the switchf
should be in one cable. The other wire? Is there another switch in
that box that it goes too, for example, to power it?


IDK what kind of switch that is, but if it's a simple screw that two
wires are under, that's not allowed. If it's a back stab it can have
two wires, but those really suck and I would not use. If it's the kind
that wires can enter from the back and go under a plate with a screw,
then I think two wires are allowed.

I would investigate the other location where work was just done and
look for a cable that heads over towards the non-working fixture.
Look for a neutral that's not connected. Even if it looks connected,
eg has a wire nut, take it off, make sure they really are twisted
together, etc.






This is the switch for the light that does not work?

The "two are charged" when the switch is not flipped, but are both
charged when the switch is flipped?

Yes and yes.



Is there more than one switch controlling the light in hte laundry
room? Not very common but would account for there being 3 wires to the
switch.

No.

Alternate question, are the two that are charged directly conneded
outside the switch, by a continuous piece of copper, or are they
connected inside the switch. (I'm assuming one is connected to the
other and the second one is hot only because it's connected. That's
probably true.)


They are connected directly to the switch, two wires going into one side
of the switch and being tightened by a switch screw, the other going to
the other side of the switch.