All incandescent lights in my house are dim.

the1percent · 02-04-2008, 06:02 PM

Friday night my microwave and stove hood fan went out. The hood fan finally started working again and hasn't went out again. The microwave wasn't running but I heard a quiet pop and the display went out. I checked and the fuse was ok. The microwave never recovered. About 10 minutes later my home lost power. The electric co. came out and changed the transformer. Since then all my incandescent lights are dim. Everything else seems to be running ok...tv, ac, dryer, etc. I called the electric co back and the guy check the voltage at the meter and he went up and checked the transformer. He said everything was fine. Anyone know what I might be dealing with? I wired the house 11 years ago when we built it. This is the first incident of this kind. i suspect a neutral wire problem, but no idea where to start. I'm almost afraid to sleep at night now for fear my house will burn down. There was no bad weather in the area so I don't think it was lightning.
Anyone??
Thanks!
Scott

joed · 02-04-2008, 09:05 PM

Are the light all constantly dim or do they vary in brightness? Measure the voltage between hots, between hot and ground and between hots and neutral.

the1percent · 02-04-2008, 09:33 PM

The lights are constantly dim. The thing is the fluorescents do not seem to be dim. ceiling fans seem to run normal speeds.
On your advice to measure voltage, where do I measure at? It has been a while and im not a professional. If you can Id need to know exactly how to set the meter and where to check in the circuit.
thank you very much!

goose134 · 02-04-2008, 10:02 PM

I would check the voltage at the panel. Open the cover (CAREFULLY!!) and use your voltmeter (hopefully digital) to read between:
1. Measure each phase to ground. That is to say, Touch one lead to one wire on your main breaker and the other lead on ground. Repeat for the other wire. These measurements should be approximately 120 volts.

2. Measure phase to phase. Take a lead and put it on one wire of the main breaker, and the other lead to the other wire of the main breaker. This measurement should be around 240 volts.

3.Measure Phase to neutral. One lead on the main breaker, the other on the neutral bar (the one with all the white wires). Repeat for other wire of main breaker. This should also be about 120 volts.

4. I know this sounds dumb BUT: Measure between neutral and ground. One lead on neutral bus, one lead on ground. This should be 0 volts. You may read some low level transient voltage. Let us know what these readings are and there might be some more we could tell you.

Andy in ATL · 02-04-2008, 10:06 PM

Quote:

Originally Posted by goose134

I would check the voltage at the panel. Open the cover (CAREFULLY!!)

4. I know this sounds dumb BUT: Measure between neutral and ground. One lead on neutral bus, one lead on ground. This should be 0 volts. You may read some low level transient voltage.

Do all that Goose says...

This one is critical.

A bad neutral is BAD!

the1percent · 02-04-2008, 10:18 PM

Thanks. I may not get to this tonight. If not, I will try tomorrow.

1. Measure each phase to ground. That is to say, Touch one lead to one wire on your main breaker and the other lead on ground. Repeat for the other wire. These measurements should be approximately 120 volts.

- This will be the two big wires coming in from the outside meter pan?
Touch one lead to one of the big wires and the other to the bar that has
all the grounds connected to it? Then repeat for the other big wire?

2. Measure phase to phase. Take a lead and put it on one wire of the main breaker, and the other lead to the other wire of the main breaker. This measurement should be around 240 volts.

- So in this case im touching one lead to one of the big wires coming in
from the meter pan and then the other lead to the other one?

3.Measure Phase to neutral. One lead on the main breaker, the other on the neutral bar (the one with all the white wires). Repeat for other wire of main breaker. This should also be about 120 volts.

- the two wires of main breaker are the ones that come directly into the house from the meter pan. Correct?

4. I know this sounds dumb BUT: Measure between neutral and ground. One lead on neutral bus, one lead on ground. This should be 0 volts. You may read some low level transient voltage. Let us know what these readings are and there might be some more we could tell you.

- so one lead on ground bus other on neutral bus?

And yes I have a digital meter.

thanks for all the help. Ill post readings when i get them. Any special protection when im touching the leads to these hot wires?

Andy in ATL · 02-04-2008, 10:24 PM

Quote:

Originally Posted by the1percent

Thanks. I may not get to this tonight. If not, I will try tomorrow.

1. Measure each phase to ground. That is to say, Touch one lead to one wire on your main breaker and the other lead on ground. Repeat for the other wire. These measurements should be approximately 120 volts.

- This will be the two big wires coming in from the outside meter pan?
Touch one lead to one of the big wires and the other to the bar that has
all the grounds connected to it? Then repeat for the other big wire?

2. Measure phase to phase. Take a lead and put it on one wire of the main breaker, and the other lead to the other wire of the main breaker. This measurement should be around 240 volts.

- So in this case im touching one lead to one of the big wires coming in
from the meter pan and then the other lead to the other one?

3.Measure Phase to neutral. One lead on the main breaker, the other on the neutral bar (the one with all the white wires). Repeat for other wire of main breaker. This should also be about 120 volts.

- the two wires of main breaker are the ones that come directly into the house from the meter pan. Correct?

4. I know this sounds dumb BUT: Measure between neutral and ground. One lead on neutral bus, one lead on ground. This should be 0 volts. You may read some low level transient voltage. Let us know what these readings are and there might be some more we could tell you.

- so one lead on ground bus other on neutral bus?

And yes I have a digital meter.

thanks for all the help. Ill post readings when i get them. Any special protection when im touching the leads to these hot wires?

It is wicked critical that you do not do this without a bit of confidence.

Safety glasses, jeans, long sleeve cotton T-shirt and a ball cap(in my opinion....Go ahead NPFa70E guys)

I have a hard hat I wear as well... but I'm a pro

Andy

the1percent · 02-04-2008, 10:34 PM

One last question. I read in another thread here where lots of members were telling a guy who had intermittent dimming that his house would burn down. I assume I'm ok since it is dim all the time?
thanks...I dont trust the Power co.

Andy in ATL · 02-04-2008, 10:38 PM

Quote:

Originally Posted by the1percent

One last question. I read in another thread here where lots of members were telling a guy who had intermittent dimming that his house would burn down. I assume I'm ok since it is dim all the time?
thanks...I dont trust the Power co.

Burn down? Dude I live in the ATL where there is a house fire every day.

Take readings and use commen sense. Feel safe? Be aggressive when it comes to safety.

Andy

LawnGuyLandSparky · 02-05-2008, 11:55 AM

Your flourescents don't seem dim because most of them have the capability of burning even when the voltage isn't right. They're not a good way to diagnose the problem. Nor is fan speed. A friend has a chandiler with 6 lights and one flourescent downlight in the middle with a CFL in it. The CFL remains full bright even when the chandiler is dimmed down to but a flicker...

Either get your voltage readings PRONTO (this can't wait for the weekend) OR hire an electrician to look into this! Do not delay - appliances burning up and lights dimming or brightening is a sure sign that you have a problem with your neutral.

Finding out where that problem is, in your panel, or your meter pan, or between the meter pan and the utility is all you can really accomplish by taking readings. If you're "iffy" about doing this than STOP and call a qualified contractor.

AllanJ · 02-05-2008, 01:34 PM

At this time you really should have nothing plugged in other than incandescent lights and non-motorized electric heaters. Especially no electronics plugged in.

Abnormally low voltage as well as abnormally high voltage can damage a lot of electronic and motorized stuff.

There is no great solution regarding the refrigerator while you wait for the electrician. The 'fridge may or may not run properly on low voltage and may or may not be damaged.

If the remaining lights stay the same (lowered) brightness as you turn others off, at least chances are the neutral is not the problem. But any super bright lights means you definitely have a neutral problem.

Intermittent dimming can mean a loose connection. A loose connection results in heat buildup at that spot, which could be at an outlet in the wall. This is what causes a lot of fires.

the1percent · 02-05-2008, 05:47 PM

Thanks to everyone for your information. I took readings at all the designated spots and all readings were normal. I went further and took readings at several outlets and a couple of bulb sockets. The reading throughout the house is 122. Even at the bulb sockets of the bulbs I suspected were dim. Given the readings, I have come to the conclusion that the transformer that went out Friday night must have been sending too much voltage to my house resulting in bright lights. I got use to this brightness and when the Poco replaced the bad transformer, the new one is regulating the voltage correctly. Having not taken a reading with the old transformer, I cannot be sure. I do have an electrician coming tomorrow, just to be sure I was taking the readings correctly.
Thanks again to everyone and for your concerns. This may also be why my electric bill had been higher than normal the past year.

Thanks again!!
BTW - The lights never flicker and I talked o the homeowner across the street who shares my transformer and they noticed their lights not being as bright also.

goose134 · 02-05-2008, 09:18 PM

Keep us posted. I hope this is the end of your problem.

AllanJ · 02-05-2008, 09:39 PM

By the way, if you measure 122 volts now and lights were noticeably brighter last week, a higher voltage back then was enough to give you abnormally short life for incandescent lamps and was capable of causing damage to electronic equipment that might show up months or years later if not already. The normal residential voltage in the U.S. and Canada is 110 to 120 (and 220-240 for some large appliances).

goose134 · 02-05-2008, 09:54 PM

Nominal voltage varies based on a lot of factors. In my house it's 126volts. My neighbors got damn near 250 between phases. But I look outside my alley window and there's the transformer. Guy down the street may not be so high. There is an acceptable range of voltages to expect.

One of the things that was concerning me about this problem was a phenom. known as the 'floating nuetral'. This is caused when a system does not have an equipotential at ground. Usually caused by improper bond at subpanel, incorrect grounding methods, or simply over grounding. The results are not hard to see: fluctuating light levels, motors running at odd speeds, gizmos burning out etc. The voltage will tend to 'wander between low and high points that are WAY out of synch with normal operating parameters. This is because voltage has no EVEN potential at which to establish a reference point (also called nominal voltage)

I'm sorry I'm rambling again. Someone asks a simple question and blah blah blah.