odd behavior from a light switch
cutterhead
| Posted in Energy, Heating & Insulation on
Just today one of the light switches in my place started acting strangely. There are two lights wired to the switch and when the switch is turned “on” one light turns on and the other off. When the switch is turned “off” they reverse. So, one light is always on. The place is just a few months old, so the wiring is obviously new too.
Any ideas???
Replies
Sounds vaguely to me like they have wired the switch to control the neutral and the second light has a ground fault. Flipped one way the current returns through the switch. Switch off the current finds its way through he ground fault and lights the second fixture.
Sounds like a multiple fault issue. Definitely a fault in the wiring. The details are not clear without doing some testing.
Odds are that when you say the one fixture is off it is still getting some voltage but not enough to light the bulb enough to notice.
New house, call the electricians back. Their fault and their problem. No need to tell them squat. If need be give the inspector a call. He or she might want to know what sort of wiring these folks are doing so their jobs can be surveyed more closely.
People who don't know what they are doing need to stay the hell away from the electrical work. Usually it is just an inconvenience but simple electrical problems can and do cause fires and get people injured or killed.
Get it taken care of ASAP. If all else fails call your own electrician and back charge the original contractor. Electrical problems don't normally heal themselves or get better on their own. The symptoms may go away but they always come back. Often with a vengeance.
People who don't know what they are doing need to stay the hell away from the electrical work. Usually it is just an inconvenience but simple electrical problems can and do cause fires and get people injured or killed.
You are right on there. Not to hijack this thread, but I went to install a few cabinets for a guy, and a previous "handyman" had tapped into an outlet to add 2 outlets higher up. I was to cover the outlet he tapped into, since it would be behind the cabinets. I of course cut an access hole in the back of the cabinets, but in disconnecting the original outlet, I noticed that the previous hack had used 14 gauge wire connected to the original 12 gauge wire. The new outlets he installed were 20 amp receptacles. I checked the breaker, and yep, you guessed it, 20 amp breaker.
So he had 20 amp receptacles connected with 14 gauge wire to a 20 amp breaker.
I told the homeowner that this is a problem, and what could possibly happen.
Boy was he pi$$ed! He called the original handyman, and chewed him a new one. Not real happy that this hack put the homeowner, his wife, grandkids, and house in jeopardy.
Turns out this homeowner is the wrong guy to have mad at you. Not only is his son an attorney, but he (the son) was head of some association with 40,000 attorneys!
I fixed it all up for him and made it safe, and he was happy. He couldn't thank me enough for bringing it to his attention. He said I didn't have to do that, that I could have just installed the cabinets and been on my way. I told him I have to sleep at night. No way would I just walk away form a problem like that.
That's my quality control with electrical. Can I sleep at night knowing what is there?
Problem is, like you said, some people don't know enough to know that it is wrong, and I'm sure they sleep fine. They should practice electrical in their own home; that way Darwin will weed them out so they don't kill any innocent people.Pete Duffy, Handyman
Thanks guys. I figured it was going to be a call back for the electrician but was hoping that maybe it was an obvious fix that wasn't obvious to me.
The problem with the area the house is in is that there's so much new housing going up that the Darwin effect doesn't weed out the lousy subs - there's more than enough work for even the bad ones.
Another possibility is that a3 way switch was installed. 3 way switches do not have do not have "FFO" and "NO" molded in the switch lever.
~Peter
Only 12 days left for the great Seattle-Tacoma earthquake
Re:"Another possibility is that a3 way switch was installed."I hadn't considered the possibility of a three-way switch. With a single switch if both switch-leg cables were driopped into the box a three way would be easy for a hack to miswire. Hook the feed to the common and the switched-legs onto the other two terminals. Make up all the whites together and all the grounds together. It would function as he described.If there were two three ways and the travelers were in either light boxes with the feed it could also be screwed essentially the same way. One light hooked to each traveler in the middle and the hot feeding both switches from the middle. In this arrangement you could control either fixture alternately and have one or both on by working both switches. The one thing you couldn't do would be to turn both off. Why anyone would run the cables that way remains to be seen. There are a lot of ways you can run the cables in each case to get either situation, one switch or two, to work. Some are simpler, use less cable or wire, distribute box fill more evenly and/or are more transparent as to how to hook up later without taking notes. In each configuration of cables there is pretty much only one correct way to make connections. Problem is there are many ways of screwing it up even if the cables are run correctly. All of this speculation. It would be interesting to find out. It is hard to overestimate how bass ackwards people can do things when they don't know better and/or don't care enough to find out or, at the very least, check their work.
I had started to respond with a suggested of a 3-way switch, but noticed the details."Just today one of the light switches in my place started acting strangely."JUST TODAY.So unless he just installed bulbs in one of the fixtures then a 3-way switch problem would have been noticed from the begining.And I hope that he does come back with what the problem was.
Yes, that's the kicker, it just started. I've done enough wiring to do basic stuff, but I don't know enough to diagnose this type of thing. So, tomorrow I call the builder. If I find out what the problem is I'll post it here.
> It is hard to overestimate how bass ackwards people can do things when they don't know better and/or don't care ....
Very true. I've found some splices in our valley house where the original electrician stripped a whopping 3/16" of insulation before cramming the wires in the wire nuts.
Given that the OP has an original craftsmanship problem, it may be a better idea to do a whole-system tuneup than to try to troubleshoot individual defects. Turn everything off, open all the boxes, check/tighten/replace as needed, document where things run, and what breakers they're on.
-- J.S.
Go and get an electrician its that simple
You can make it fool proof but not idiot proof
Are these lights hard wired, or plugged into switched outlets?
If this started "just today", then something has changed. If they're plugged into switched outlets, then maybe they've been plugged into the other half of the outlets, and maybe half the outlet is normally on, the other half normally off, but I can't imagine why. It would take a 3 way switch wired creatively to do this, anyway. Pull the switch out and look at how it's wired. That may give you a clue.
No matter what, you have a strange wiring problem. First step is to find out what else is on that circuit (or circuits), and unplug / isolate them. Something has changed, and you have to work backward to find out what. Think, and ask everyone in the house - what did they do yesterday, that might affect that circuit. Did someone plug in a radio in the garage? Something has happened to cause a change. Find the change, and you'll be close to finding the problem.
I once lived in a house that had what seemed to be a three way on a basement light, but it was in reality just two normal switches. Sure, you could turn the light on from either side, but you could only turn it off by using whatever switch you turned it on with. It took me a while to find out what the problem was, simply because when I pulled out the switch, it didn't twig that neither of them was a three way.
The builder spoke with my wife after looking at the problem and said it was orginally supposed to be wired with two switches for the two lights - and that the electrician had wired both into one switch. Said it was buggered up and that he would fix it. Doesn't explain why it would suddenly start acting the way it did months after the wiring was done. I'm not getting a warm fuzzy here.
My first guess was that it was three way wired wrong, but if this just started happening...I'm not so sure. Any way you look at it something's wired wrong and it needs to be corrected. Good luck.
Yeah, demand (politely) that the builder send an electrician to fix this. Something is fairly badly messed up.