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brand new home w/ electrical dimming throughout - help!

Posted by graceshan (My Page) on
Thu, Nov 8, 12 at 22:08

We had a new custom home built and moved in 3 months ago. It's 2500 sf with a 750sf apartment above the garage. Since we've moved in many of our lights have been dimming rather annoyingly throughout the home and apartment. We've narrowed down some of the times to when the heat pump goes on, if the vacuum is going, if a saw is being used, if a fan is plugged in and running, if the dryer is running, etc., etc. The lights that dim are usually right around whatever else is being used at the same time in the house. We have many Cree LED can lights throughout the house as well as regular lighting too. The dimming happens with both types. The electrician came back out and said everything looked fine on his end and to call the utility company. So we did and they did some testing and upgraded the wiring outside to 4/0 and said the transformer was already recently replaced so we should be good with the outside wiring. This changed nothing and the dimming is still happening. So we contacted the electrician again and he said he didn't have the proper equipment to test it for a longer period of time. He wants us to go through each switch in the electrical box and try to isolate the problem ourselves. I'm wondering if anyone has a clue as to what's really going on here and why nobody can seem to fix it? Also wondering if this dimming causing problems to our electrical? I'm nervous about the effects on our appliances, etc. Is this dimming causing our electrical bills to be higher? They sure feel like it. Thanks in advance for any help!
Shannon


Follow-Up Postings:

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RE: brand new home w/ electrical dimming throughout - help!

I'd suspect a loose neutral in the works.

Good troubleshooting:

http://www.doityourself.com/forum/electrical-c-d-c/82157-loose-neutral-explanation.html


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RE: brand new home w/ electrical dimming throughout - help!

I'd call the electrician back and remind him it's HIS job to fix it. I agree, it sounds like a loose neutral, and HE ought to check everything til he finds it.

If he continues to stonewall you, I suggest you tell him you plan to complain to the licensing board in your state.

I hope you don't have any more issues. It IS a potential fire risk, as is any loose connection.


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RE: brand new home w/ electrical dimming throughout - help!

The odd thing is that I had researched online and saw that cause of dimming can be a loose neutral so I asked him about that and he insists it's not and said he had installed some type of thing (I forgot what he called it) that would not let that happen. He also said the dimming shouldn't be a fire risk (I asked him that too). I'm wondering if I should just get another electrician out here to check this out.


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RE: brand new home w/ electrical dimming throughout - help!

"--cause of dimming can be a loose neutral so I asked him about that and he insists it's not and said he had installed some type of thing (I forgot what he called it) that would not let that happen"
I know of nothing that can be installed to prevent a loose neutral. Wear tall boots when talking to that person. Ask him for the manufacturers name and part number. We want to know more about this magic device.


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RE: brand new home w/ electrical dimming throughout - help!

Ya, there is no device that will stop a neutral from becoming loose. If there was, since there is a neutral at every plug in your house, there would have to be one "device" at each location.

He sounds like a sub that has "moved on" and doesn't want to have your job hanging over his head.


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RE: brand new home w/ electrical dimming throughout - help!

Any circuits getting brighter?
That is one of the hallmarks of a loose neutral.
The '0 V' of the neutral moves from the middle of the 240 V, so one line gets higher voltage while the other line is lower.

If ONLY dimming a loose hot or overload, all the way to the pole transformer is possible.

You may need to complain to the POCO.


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RE: brand new home w/ electrical dimming throughout - help!

I just texted him to ask if he was 100% absolutely sure it wasn't a loose neutral and he wrote this:
"I really do not think so because the problem is thru out . And if that was the case it would be more localized unless it was at the main service which I checked."
Does this sound right? He did check the main box briefly when he was here a couple months ago. Would that be sufficient to check for a loose neutral?
He lives 1.5-2 hours away so I think he's trying to do what he can from a distance... Which is why he asked If I would go through all the breakers and check to see if the dimming was happening one at a time.


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RE: brand new home w/ electrical dimming throughout - help!

The lights aren't really getting brighter. They just dim for the duration of whatever is happening at the moment. If the heat pump goes on, then they dim/surge for a second and then go back to normal. If someone is using a vacuum, then they dim for the duration of that usage and then go back to normal. It happens throughout the entire house & apartment so it's not localized anywhere specific. But it only happens near whatever is being used, except for some reason the heat pump surging/dimming lights which I notice in my bedroom every single night and morning (because it's the only place I'm at consistently at the same time) but my bedroom isn't located near the pump so I'm not sure why it happens there.

The utility company had recently installed a new transformer and they have been out here several times to check and test everything.


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RE: brand new home w/ electrical dimming throughout - help!

Hmmm....

Kinda thinking out loud.... would it be beneficial to install a 20A breaker in the panel and temporarily splice a 12/2 (w/female 3 prong end) onto leads from that breaker, the neutral bus bar and ground bar? then, plug a lamp/light into the splice to see if it dims?

Or... as a process of elimination, turn off all the breakers, turn one breaker on and plug a vacuum in on that circuit along with a light and see if it dims. If it doesn't, turn on another breaker and test again and keep doing until you see a causal effect.

Just taking shots in the dark on this one. No pun intended. :p


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RE: brand new home w/ electrical dimming throughout - help!

Get a plug-in voltmeter, available for cheap on eBay. Plug it in to a receptacle and observe voltage variations, if any. There is a possibility that you may be unusually sensitive to variations in the brightness of lights. Very slight and very brief dimming is not unusual when large loads start.


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RE: brand new home w/ electrical dimming throughout - help!

Bus driver: I can rule that one out because the lights were dimming so much when the electrician was here installing our speakers that he actually asked me to turn them off as they were bugging him. So he KNOWS how much the lights dim and has seen it firsthand. Our builder has also seen it as well as other workers. So we don't have a problem with that aspect of it.

tjdabomb: That's what the electrician is asking us to do... process of elimination throughout the house. I'm willing to do it for him but just first wanted to be sure there isn't a loose neutral or other factors involved.

Thanks for the responses. It helps to have others chime in and think out loud.


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RE: brand new home w/ electrical dimming throughout - help!

"the lights were dimming so much when the electrician was here installing our speakers that he actually asked me to turn them off as they were bugging him. So he KNOWS how much the lights dim and has seen it firsthand. Our builder has also seen it as well as other workers.

Geez Louise! If that's the case, it sounds like first you need a new electrician to locate and correct the problem, and then unfortunately, probably a lawyer.


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RE: brand new home w/ electrical dimming throughout - help!

Grace - have the electrician do it. The mere fact that this issue is occurring has to do with a installation that has serious problems. You shouldn't have to troubleshoot his problems, he works for you, not the other way around!!!


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RE: brand new home w/ electrical dimming throughout - help!

"Grace - have the electrician do it." I agree- a little bit. But he may be only marginally competent-- or apathetic.
In the case of one huge power company with which I deal, a business problem with them-- not an electrical issue-- took me two years to resolve-- and then only "sort of". Finding someone who was: 1. Competent, 2. Caring, and 3. Empowered to deal with the problem was almost impossible. Most of the thinking and effort was mine.
Keep on making observations, collecting data and keep good notes!


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RE: brand new home w/ electrical dimming throughout - help!

Ya, if not the original electrician, then definitely a different electrician.


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RE: brand new home w/ electrical dimming throughout - help!

I feel like he'd come out and end up leaving saying he can't figure it out like he did before. I feel like I'm more vested in getting it figured out. Maybe it's time to find another electrician...


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RE: brand new home w/ electrical dimming throughout - help!

Have you tried complaining to the POCO?

They will install a temporary logger that will look at what THEY are supplying.

If they come back with a problem it does not cost you anything.

If they come back that everything is within alloawable levels you should get soeone that knows what the h*ll they are doing to start fidning the problem.

If the dimming is that severe it should not be all that hard to track it down with a volt meter and a decent size load.

I still use space heaters even though I have an expansive electronic load that goes up to over 300 amps (at anything less than 1,000 V).


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follow-up re: brand new home w/ electrical dimming throughout - h

So I decided to do the electrical box testing for the electrician and went through each switch one at a time and then plugged in the vacuum to see if the lights surged. They surged every single time. The other thing is that we have an apartment above our garage and he put in a main panel for the main house and a secondary panel for the apartment (both panels are side-by-side in our garage). But the dimming/surging is happening in both the apartment and house so he says he can rule out any electrical panel issues based on that alone. So I had the utility company come out again and test everything. After a week long test they said everything going into our meter is within allowable levels and that the transformer is fine too. They said to talk to my electrician about the panel. So I told this to the electrician and he went to the utility company directly and spoke to the engineer. He found out we have 9 houses on our transformer and when our heat pump goes on it takes up 75% of the load (from the graphs they gave him). So he deduced that it's a utility problem and not a house problem. I then called the engineer myself and she said that the levels for the transformer and wire into the house is fine and that they actually upgraded the transformer in addition to the 4.0 wires. She recommended I check the amps on the panel as they might not be adequate enough. The amps on the main panel are 200. I have no idea how much is set aside for the apartment panel from this. But there is a switch to the apartment panel in the main panel too.

Both the electrician and engineer said we should get a soft-start for the heat pump (which I agree) but it's not just the heat pump that causes the lights to flicker/dim/surge. It's other things too.

SO I'm no better off and the electrician checked the panel again for about 5 minutes and said everything looks fine to him. Any thoughts on this new information?

I need serious help!


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RE: brand new home w/ electrical dimming throughout - help!

I would guess that your voltage from the utility is at the lower end of their "allowable limit," which around here is 105 volts. We routinely drop to 105 during times of peak demand. Is your problem occuring all the time, or only during high demand times? (Extreme heat or cold)
Are there a lot of new homes in your area? In my area of Massachusetts, the utility still has not caught up with upgrading local distribution to accommodate new construction from a decade ago, and we're at the end of a 15 mile primary run from the substation.
I'd also question 9 houses on the same transformer. I realize that there are various sized transformers, but around here there are typically 4 to 6 houses (mostly with fossil fuel heat) on each transformer. If you're at the end of the primary run, 9 homes may be pushing the envelope. I'd ask to see the utility's report. They could be giving you lip service to avoid spending money, even though solving the problem might be as simple as connecting the transformer to a different primary line. I've noticed that more than half of the transformers around here are hooked to the same primary. (Of which there are three.) The things you notice when you're walking around, huh?


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RE: brand new home w/ electrical dimming throughout - help!

Nothing indicates that you have, personally and directly, checked the voltage with a voltmeter. I suggested this earlier. It is what I would do if I was at your premises and trying to help with the problem. One of the plug-ins will enable you to know the voltage with just a glance. Keep a written record of the values observed, date and time.
The person with the greatest interest in your situation should be actively involved-- exactly who would that person be?


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RE: brand new home w/ electrical dimming throughout - help!

bus driver: I'm afraid I'm just not sure what to look for with voltage fluctuations. I'm a full-time teacher with an 11 month old baby and I've been doing as much as humanly possible to figure this out within the time frame I have to work with. I'm thinking I should find another electrician for a second opinion, but I'm at odds with what to look for in another electrician to be sure he is competent enough to figure this out.


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RE: brand new home w/ electrical dimming throughout - help!

Are any of your closest neighbors having the same issue?? Especially any that are "fed" from the same transformer.


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RE: brand new home w/ electrical dimming throughout - help!

It's not uncommon for lights to dim (slightly) when a large motor load is turned on. It should last no longer than the time it takes to snap your fingers.

If it is a weak load or neutral service connection, the bad connection may not necessarily in your panelboard. Could be inside the meter box. (The utility would need to pull the meter to check this). (I also agree with the others, it sounds like a weak neutral connection to me as well).

There also is the (weak) possibly there is a high resistance in your systems earth ground (grounding electrode or grounding electrode conductor). You could talk to your electrician about investigating this and, if necessary, adding a 2nd grounding electrode.

One other thing to look at is exactly what voltage you are getting in your home. You can plug in a inexpensive voltmeter (I've seen them as low as $5) into one of your electrical recepts and check the voltage. It should read somewhere around 120 volts.


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RE: brand new home w/ electrical dimming throughout - help!

All you have to do is glance at it and record the reading, date and time. That may yield some helpful information (to an expert) after a large number of such observations. Do you want to have them there for hours doing this- while you pay them?

Here is a link that might be useful: Voltmeter


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RE: brand new home w/ electrical dimming throughout - help!

Thank you. I ordered the voltmeter you linked to. I can do this type of research for sure.
I'm having a big holiday open house in 2 weeks and I'm planning on asking all my neighbors about it. We built our new home in the same spot as our old house and never had any problems with the old house...


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RE: brand new home w/ electrical dimming throughout - help!

"We built our new home in the same spot as our old house and never had any problems with the old house..."

OK, so you may not think this was important, it has a lot to do with identifying your current problem.

While your description is subjective, and other posters have suggested means to obtain objective measurements, it does not seem to be the approach the electrician and others are taking here.

You really need to bring another reputable electrician into this to identify the cause of the problem - this ain't rocket science!

You indicated that your current electrician who installed the wiring saw the problem, was irritated by it, and could not identify the cause. He is obviously an idiot!

Don't know if you live in a "good-old-boy" town or county, but you really need to find an unbiased knowledgeable opinion here.


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RE: brand new home w/ electrical dimming throughout - help!

" plugged in the vacuum to see if the lights surged. They surged every single time. "

that would actually be a 'sag' not a surge.
You might get further with the POCO of you describe the problem correctly.

Surges are INCREASES in voltage, the lights would get brighter.
Sags are decreases in voltage, the lights get dimmer.

"a soft-start for the heat pump"

That would be a 'hard start' kit. It allows the unit to start up faster and minimizes the duration of high current pulled at start-up.

It really sounds like the POCO did not put in a large enough transformer.
KEEP ON THEM.

you want a recording volt meter IN your house for a few days.
Look up CBEMA curve if you want to see what typical limits are for power quality.

It sounds like there is nothing you can do except band aids (like a hard start kit) to make up for the POCO's sagging voltage.

This post was edited by brickeyee on Sun, Dec 2, 12 at 10:36


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RE: brand new home w/ electrical dimming throughout - help!

Update: so PUD upgraded the transformer again and we had a hard start kit installed on our heat pump. Nothing has changed. The lights are still dimming and SAGGING (thank you brickeye). There are 9 people on our transformer and none of the neighbors are having issues. The PUD engineer said all levels into our home are within acceptable limits. Our contractor said the electrician now thinks (without testing) it's the bulbs or dimmer switches, yet it's not one type of bulb nor is it exclusive to the dimmer switched lights. Am I crazy to think the lights should work properly in a brand new home that had built from the ground up? I plugged in my voltmeter a few places and didn't see any real fluctuations, but I just can't sit around and watch it all the time. I'm not even sure I know what I'm looking for. Can another electrician actually come in and test for the problem and figure it out?


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RE: brand new home w/ electrical dimming throughout - help!

Not many electricians have logging voltmeters, but that is what it sounds like you need.

Try calling around and see if you can find someone that has one.


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RE: brand new home w/ electrical dimming throughout - help!

http://www.helium.com/items/1549725-lights-dimming-in-my-home

I have the same issue! Have you found a solution? Above is a link to a possible cause. I'm going to investigate it further to see if its is the problem.


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RE: brand new home w/ electrical dimming throughout - help!

No we have not yet. The utility company just upgraded the transformer again last week but it had no effect on the dimming. Our contractor has gotten involved and he's requesting info about the line from the transformer to the house and if that's not the issue, he has advanced electrician who is going to come in and do testing. Hopefully we'll get it resolved one of these days. Here's a video of some dimming that happened after the transformer was upgraded.

Here is a link that might be useful: Video of dimming lights


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RE: brand new home w/ electrical dimming throughout - help!

Our contractor said the electrician now thinks (without testing) it's the bulbs or dimmer switches, yet it's not one type of bulb nor is it exclusive to the dimmer switched lights.

Are you sure that it happens on lights that aren't on dimmers? Eg. does the light inside your refrigerator flicker like that?


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RE: brand new home w/ electrical dimming throughout - help!

You video appears to shoe\w at least some brightening.

Brightening is a real hazard and a danger.

It means the voltage is going higher than it should be.

Cal the POCO and tell them you have lights that are brightening, the same with the electrician.

The POCO WILL get off their butt and investigate then.

Are you using the same fed on the new house as the old?

Are your electrical loads larger tan they had been?

Has anyone actually tried to tighten the connections in your panel? (it can easily be done with the correct insulated tools, is is only 120 V to ground).


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RE: brand new home w/ electrical dimming throughout - help!

I believe we have 2 types of dimming/surging going on. The type like the video I just showed you that happens completely randomly on ceiling lights throughout the house (they might all on dimmers but different types of lamps/bulbs) and then the type of dimming/surging that happens each time the heat pump goes on or a hair dryer is plugged in or someone is using power tools. These lamps are not all on dimmers. Some are just stationary lamps. Here is a video of a bedside lamp (not on a dimmer) doing it when the saw is turned on/off outside on the front porch.

Here is a link that might be useful: video of dimming lamp (not on a dimmer)


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RE: brand new home w/ electrical dimming throughout - help!

If there is actually brightening of the the lights and not an artifact of the camera you should go shut the main off, cal the POC and your electrician,

The mid point of the 240 V moves around when a neutral is not solidly connected, and the 120 V on each leg can approach 240 V depending on the loading on each leg.

Every time the voltage goes above about 132 V it cases damage to many loads, especially motorized loads.

Momentary sags do not have the same impact, but if repeated enough times can damage 120 V induction motors (their current draw rises as the voltage sags if they have a constant load like a forced hot air fan).


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RE: brand new home w/ electrical dimming throughout - help!

In early November 2012 I suggested that you get an inexpensive plug-in voltmeter and observe some readings. There is no post indicating that ANYONE has done this. Multiple posts on a forum does not cure problems in the absence of any other action.
I wonder why I even bother to try to help.


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RE: brand new home w/ electrical dimming throughout - help!

Bus driver... I only posted again because someone else posted and asked me if the situation had been resolved as they are having a similar issue. I'm not here just to whine or complain but in hopes that someone else might be helped too. I did actually post and say that I purchased the voltmeter you recommended and observed some readings, but I did not notice any fluctuations (got tired of looking at a voltmeter when I really don't know what's going on with it) and eventually went to the head general contractor who built our home and told him that we need to get a second opinion on the matter. I hired him to build our home and take care of this kind of stuff and I don't feel I should be the one sitting around trying to figure out what's wrong. So he started getting actively involved and is now taking care of the situation. I was just posting an update and thought I'd show the videos that I took for him as well in case it helped clarify if the other person is having the same problems. I do appreciate the help I've received here and I'm sorry that my multiple posts have bothered you. Feel free to click the "no longer receive notifications" button and you won't be bothered any longer.


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RE: brand new home w/ electrical dimming throughout - help!

When the onsite "experts" failed to diagnose and correct the problem, the request for help appeared here and it was presumed to be sincere. But the suggested effort apparently was just too much trouble. No observed voltage readings were ever posted here, so only the onsite eyes ever saw them.

My general approach is to diagnose and fix the problem-- then one can identify and assign blame at leisure.

This post was edited by bus_driver on Tue, Feb 19, 13 at 11:19


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RE: brand new home w/ electrical dimming throughout - help!

I saw your first video and if might lights did that, I'd be freaking out.

I have an 'inexpensive' LED flood light in my bathroom that can go up and down like that. I consider it to be the light, since I have an incandescent next to it that does not do the same thing.

I would not worry that much about the saw dimming the lamp. My hair dryer dims the lights in my bathroom. I don't consider that such a big deal.

I have used this WattsUp? meter before. It is a logging meter and costs a bit more (quite a bit more), but the advantage is that you don't have to sit and stare at it. You can import the data into their app software and generate a nice graph. It will also save the high and low values.

Here is a link that might be useful: Watts Up Pro


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RE: brand new home w/ electrical dimming throughout - help!

You need to find someone with a line voltage data logger and install it for 24 hrs. I would think the POCO would have them.

I wonder if there isn't something wrong with your panel (something with the ground).

The reason I say the panel is because the problem is throughout the home.


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RE: brand new home w/ electrical dimming throughout - help!

This is no more than a guess.

I think that the consensus is a neutral problem.

I think the grounded service conductor has been compromised.

It may be a loose connection, or physical damage, or an unseen splice.

When the new house was built did the service change in length or direction or type? (overhead vs underground)


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RE: brand new home w/ electrical dimming throughout - help!

The dimming of the table lamp when the saw starts and the flickering of the ceiling lights seem like two completely different symptoms to me. I'm not sure why everybody seems to assume that they are a single problem.


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RE: brand new home w/ electrical dimming throughout - help!

The dimming and flickering are quite likely related. Triac dimmers don't like bizarre waveforms and also create their own. Many of the things that cause dimming of non-dimmer-controlled lights cause flickering of dimmer-controlled ones.

The same is true of electronic ballasts: many fluorescents will flicker when the line voltage dips, even if the "dipped" voltage is steady.


graceshan, what various people wanted you to do with the voltmeter was not try to do anything yourself, except read the numbers during "normal" (not dimming) situations, vs during times when the lights are dim (you said it stays dim the entire time the vacuum is turned on, so this should be easy...) and report the numbers here... Nobody expected you to know what to make of the numbers, merely to come back here and report what they were.


Oddly enough, I posted a musing a while back about why it seemed like hospitals in my area had very erratic electrical systems where lights would flicker and dim randomly, and there always seemed to be an unexplained relay clicking in an unexpected place... perhaps whoever wired my local hospital is also the guy who wired your house...


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RE: brand new home w/ electrical dimming throughout - help!

"WattsUp? meter"

Very unlikely to catch voltage sags and surges.

this is a voltage problem. Not a power or energy (Watt-hour or or watt)

The filter built into most watt meters to give stable readings removes shorter transients.

Most are not fast enough to even catch a motor starting surge or the resulting sag in the voltage.

The problems may be related if their is a neutral problem or inadequate transformer.

Even power circuits can 'ring' when large transients occur.
It is not like there is a lot of voltage regulation spread around the distribution network (other than adding capacitor banks to shunt voltage surges).


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RE: brand new home w/ electrical dimming throughout - help!

Is it fixed yet?????? If so, what was the problem? It would be helpful to post the results.


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