I moved into a new home (new construction) about a month ago. I have noticed a couple things that I consider to be weird with the wiring and am wondering if this is normal or not.
First, when I use an iron the lights dim for a split second each time it kicks in. I think the way my iron works is that it heats up to a certain temprature and then slowly cools down. Once it gets to the low end of it’s acceptable range it kicks back in and heats back up to the higher temperature again. Each time the iron makes a little click noise the lights quickly dim.
Second, and this is more annoying since I watch tv more than I iron, whenever almost anything electrical in the house is used there’s a little bit of static on the tv screen. I notice it when the heater turns on, when I use the water filter on my fridge, when the fridge is running, when I use a mixer or vacuum cleaner. I have never experienced this anywhere else I’ve lived to this extent. I remember this would happen when I was a kid and my mom would vacuum but that was a house built in 1950 and, I guess, expected. I don’t expect this to happen, and even more frequently, in a brand new home. Anyone have any thoughts on this?
I will point out that right now I am using an antenna for the tv. On Saturday I will get the cable hooked up. Could the electrical things just be interfering with the signal because it’s coming through the air and as soon as I get cable it won’t be a problem anymore? This is my hope but I think it’s just wishful thinking.
Thanks in advance for any input.
GE
Replies
You have a bad connection in the service. Depending on where this is it can be very danagerous.
Specially if you notice any light getting BRIGHTER instead of dimmer. That is caused by a bad neutral conntection.
The problem can be either internal or external (power company). And on older homes I suggest calling the power company first as there connection are in the weather and more often to fail.
But in this case it is a toss up.
I would call both the builder and the power company. And don't let either off the hook until it is resolved. And it should be resolved in a couple of days.
Depending on the specifics of the problem it can lead to house fires and exploding light bulbs among other things.
Re: "You have a bad connection in the service."I think your onto something. A loose connection is also the first thing that popped into my head. Not sure if it is in the service or a branch circuit. This might be a good time for him to try an old trick: Get a small, portable and battery powered, AM radio. The old style 'transistor radio', a pocket sized unit often fed by a single 9v battery and having a telescopic antenna.Set the unit while some distance from the house and with the antenna extended to an open spot on the radio spectrum. A frequency without a radio station and just a bit of fuzz, a little noise lets you know the radio is working, is ideal. Note that spot on the dial. Go back to the house and walk around with the antenna extended. Your problem could be in the service. It could also be in a branch circuit and radiating through the system. Turning off circuits while tracking the static can localize the issue. Try it with various circuits on and off. Turn on the TV and note any noise that coincides with static on the TV screen. Loud static, hissing, growling, popping and the sound of 'frying bacon' are strong clues. As you walk around note where the noise gets loudest. Play with switches, tap receptacles and turn off and on loads. Pointing the antenna and lowering the volume often allows you to localize a junction box or panel. I have had a lot of luck using this .Principle is that an electrical arc throws off square waves that interfere with AM radios. Arcing can be detected at considerable range by an AM radio. An ultrasonic leak detector works better still but few people have one of these in their toolbox. This is a good trick for electricians. Looks real high tech. Almost magical as you wave the antenna around like a wand. Big 'wow' factor. That is if it works. Hero or goat. Seems there is little in between.
He said that the interference with the TV was caused by a number of different items, that is why I assumed problems with the service and not a branch.I used the AM radio trick on at my house. Forgot what the problem ended up being. I think maybe it was a bad ballast.Last year I was back in Lousiville for Christmas and was at ny nice's and notice the lights flickering.I carry just a few general purpose tools with me (adj wrench, pliers, a couple of screw drivers and utility knife). But I also have a #5.59 radio shack DVM that is in a small notepad style.Anyway I get that and go over to there house and make a could of measurements and tell them to call LG&E (Dave Richardson's outfit) that they have a bad neutral. And when I got back the next day they had just finished fixing it.
Good story. Stopped a potentially dangerous problem.I seldom go anywhere without some tools. Feel naked without the basics. I always throw in a Klein bag with a few tools and a few assorted wirenuts into my suitcase. Of course I have a full set on the truck. Got a Leatherman on my belt. Only problem with a leatherman is they are a pain, literally, to use on live circuits.Funny how being an electrician changes things. I go over to a friends house and her light flicker and I'm in troubleshooting mode. Things most people don't notice hang me up. The tangy, acrid smell of burnt electrical equipment and smoked Bakelite. I can smell it in seemingly minute quantities that many can't detect. Almost more a taste. I smell it and automatically start looking for a problem. Often while people look at me like I'm nuts.
GE,
Well, it's normal to have a slight flicker in incandescent lights when a big demand for power occurs in a circuit. By flicker, I mean a virtually instantaneous dimming of the light(s) which then return to normal.
The flicker is due to a drop in the voltage. It's like a drop in the shower water pressure when water is turned on elsewhere. And like with the shower, the closer the new load is to the point of interest, usually the greater the pressure drop. So the shower gets hotter when someone flushes the toilet, 'cuz the toilet is using cold water and the shower and toilet are relatively close to one another in the water supply set up.
I think a clothes iron is a moderately big load, maybe 500-700 watts. So if the lights in that room are on the same circuit, the power draw of the iron cycling on and off (you're exactly right on that), will cause a flickering in the lights. How much of a flicker is normal, and just has to be tolerated, is the question.
A central air conditioning compressor or a well pump will do the same thing, and because the power draw for a motor starting under mechanical load is really high, it will normally affect the lights in the whole house. A vacuum cleaner has a relatively big motor, and so when it's turned on, there is usually a flicker in the lights on that circuit. Even is a house with a well-designed electircal system, and good supply voltage from the power company, flicker from these causes is normal. You just have to learn to live with it.
But, there are things that make flicker worse. Having lights and receptacles on the same circuit, for one. Also, flicker will be worse than it has to be if the system is close to capacity. For instance, using smaller gauge wire for the circuit, especially if the circuit runs far from the breaker panel and has a lot of load on it normally. These things make it harder for the circuit to supply all the power that's needed, especially at the instant that another load is turned on. So the electrical pressure drops when something else draws power from the circuit. Flicker may also be due to poor connections in the breaker panel, or the branch circuits.
There are other possible causes that are systemic, like insufficient supply from the utility transformer, a bad connection at the utility transformer, or a bad connection in your service (meter base and breaker panel). This would affect everything in the house, although the stuff on the circuit with a heavy load coming on would be affected more.
How big is the house? What size is the electrical service? How loaded up are the branch circuits? How robust is the power company supply? These things factor in when trying to identify the cause. To really nail down the cause(s), the best way is to use a recording voltmeter (or at least one that records minimum values) to take measurements at different points in the system.
I've been party (as a consultant) to situations like yours. One was very interesting-- a multi-million dollar house, lights flickered throughout when even a moderate load was turned on. The builder called in two master electricians (including the one who wired the house), and using their eyes to judge, they couldn't agree whether there was any flicker. The obvious things were done, checking connections in the panel, etc, with no improvement.
The electric utility was called. They claimed to have measured voltage at the transformer supplying the house, said things were normal, and disavowed any responsbility. I came in and made some measurements with recording voltmeters, that showed significant voltage drop at the meter when a moderate load came on line in the house. There are utility company guidelines as to how much supply voltage drop/light flicker ought to be "acceptable" to the customer. These were exceeded in this case.
When presented with my findings and the data, the utility got serious and started looking at their supply transformer and service lateral (underground supply lines to the house). Lo and behold, they found some bad splices which they repaired. Problem solved. Oh, and the utility never did share the data from their voltage measurements (if they ever did any). They were hoping that the complaint would just go away. Isn't untility de-regulation great?
As far as your case, with a new house, start with the builder and see if they can get the electrical contractor back to check the house wiring for obvious problems. If that turns up nothing, it might be design problems, in which case adding a new circuit or two where heavy loads are plugged in, might help. Or it could be a supply problem on the power company's part. Don't expect the general contractor or his electrician to be as sensitive to the flicker as you are. And if the electrician rules out the house wiring, thereby pointing the finger at the PoCo, don't expect a lot of action from the power company unless you have some hard data showing that the problem is not in the house wiring.
Finally, recognize that you'll have to accept some flicker.
Good luck,
Cliff
Edited 12/16/2004 1:57 pm ET by CAP
A Rowenta DM-880 iron draws 1400 watts!
Ah. Been a long time since I ironed (like never). Well, I used to use a little clothes iron to wax my wooden skis.Anyway, Bill's point about this possibly being a dangerous situation is well-taken. If there's dimming of some lights and coincident brightening of others (on other circuits), that's a sign of a bad neutral. And that's very bad. A good electrician with a simple voltmeter ought to be able to confirm a loose system neutral in short order. Then if your sparky calls the power company (PoCo) reporting "a loose neutral on the PoCo side of the meter", you should get a fast response, namely a prompt visit from a line/fault crew.Good luck.Cliff
Edited 12/16/2004 2:19 pm ET by CAP
I've tested circuits using a digital voltmeter and a 2000 watt incandescent lamp load. Read a receptacle under no load, then turn on the light, and read again. The steady state drop should be under 3%. During warm-up, resistive loads like irons and incandescents pull a starting surge much larger than their steady state load. Motors, too, have a starting surge, but for different reasons. A brief dimming (or brightening on the other leg) due to a large load's starting surge is normal.
Here, the utility standard is that they're supposed to supply the nominal voltage plus or minus 5% as measured at the service entrance.
-- J.S.
I've also had to use recording meters to get the utility to accept responsibility, typically they send a lineman out with a meter. These charachters are only loosely related to electricians and are lucky to be able to turn a meter. [if you are a lineman out there who can turn on a meter,congratulations] Try to meet with your electrician and use your various loads while he records at the circuit and at the service.