In alt.home.repair, on Sat, 21 Dec 2019 09:35:11 +0630, Oumati Asami
wrote:

On 20/12/19 21:28, trader_4 wrote:
On Friday, December 20, 2019 at 3:09:49 AM UTC-5, 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?

This test is with the light removed? You have one cable, with two conductors
plus a ground wire? By charged, do you mean that you have 120V on
both, or some other, lower voltage? What are you connecting the other
side of the meter to? Ground?


No. Tested when the light tube was in the fixture. There is no ground
wire, no neutral inside the switch box. I used a neon tester.

Clare is probably right. One of the two wires to the lightbulb is a
neutral, but if it is cut somewhere, the voltage comes in through the
hot, goes through the lightbulb and makes the part of the neutral wire
conneecte to the lightbulb hot also.

If you take out the light bulb and especially if you use a real meter,
not a practically worthless neon tester, you'll see that one side of hte
light fixture is dead. Since it is dead**, you can use the ohmmeter
part of the vom to check the resistance between the dead wire and some
other ground. If the neutral wire is cut, the resistance will be
infiniite.

**If you try to measure the resistance between a hot wire and ground,
you may burn out your meter, or even melt parts. But if you do this
often, some day you will mess up. Try not to be standing on a ladder
when you do this.

This is the laundry room. Is it finished, a ceiling?

Did the light used to work? Any work done in the laundry room or nearby
lately? Like drilling, cutting, or sawing?






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