So, funky problem.

My son goes to turn on the tv downstairs this morning. For 5 years it has been plugged into a surge protector, along with his xbox, a surround sound unit, receiver, dvd player, and a powered subwoof. None of the surround sound components have been turned on in ages, as our upstairs tv has become our main movie center. He occasionally unplugs the xbox to take it to moms, but otherwise nothing has changed.

He said that as soon as he turned the tv on (its an older 32" tube style tv) the lights dimmed slightly, then resumed power, then everything went out. The entire downstairs living room has no power (plugs or light fixtures), the light fixture in an adjacent bedroom doesn't work but the plugs DO, and the lights AND plugs in the other adjacent room work. Also, the bathroom off the living has full power. Everything upstairs is normal.

Naturally I assumed it was a breaker. Not so much. I even reset ALL of them including the master. I tested and reset all the GFI plugs (even though these rooms still had power). I went as far as to turn open up the breaker panel, turn off the main power and all breakers, remove the one suspected bad breaker, pull a matching breaker from the opposite side (my understanding is with 220, 110 is split down each side?) and tested it. No luck. But even if one of the 110 circuits was toast, why would all other breakers on that side work. I subbed in a good breaker of the same amperage from a known working circuit into the couple that I thought it could be (two are labelled "downstairs lites and plugs", which is helpful....) and still had no power on that circuit. Just for kicks, I took the wire from the bad circuit and plugged it into a known good breaker on the other side and flipped the power on - no luck. So I reconnected everything as it was originally and in my head I can rule out bad breakers.

Next I went with a popped off backstabber on one of the switches or light fixtures. I pulled a few random ones in that room (two switches, one plug, one fixture) and they're all screw type - not spring type backstabbers. All the wires appeared secure, intact, unburned, and the grounds were all secure. For kicks I gave each one a little wiggle and made sure they were tight with the screwdriver. I did NOT do this with all of the plugs/switches/wires. My assumption is that if SOME are screw style and not backstabber style, I probably don't have a popped off backstabber.

Which leads to me this: Now what?

 

Welcome to the forums.

You should determine every device on the problem circuit in anticipation of removing and checking every one of them. Once you have the devices listed you can usually follow the wiring path from the panel thru the house. On that circuit.... are there any devices working ?
The problem will be between the last working device and the first dead one.

I would go to one of the dead receptacles and check from the small prong(hot) to ground.
Then check from the large slot(neutral) to ground.

As far as the panel.... you have 240vac service with two 120vac legs. Picturing the left side of the panel..... breaker 1 is on one leg. Breaker 3 is on the opposite leg and they alternate down the entire side.

 

You have to inspect every switch, light, and receptacle on the circuit. Redo and replace all wire nuts. The problem could be at the last working receptacle on the circuit. Do you have a multimeter, preferably analog.

Terminology note: They are receptacles not plugs. Plugs are the male device that goes in a receptacle.
Tech note: your nominal voltages are 240 and 120 not 220 and 110.

 

I am fairly certain I know which switches, lights and receptacles are on the circuit, but I don't know which one is the start/end. I'm used to DC vehicle electrical systems where everything forms a closed loop. My understand, until yesterday, was that home systems were the same, so I was operating under the assumption that the problem could be anywhere in that affected area.

So when you say the problem could be the last working receptacle, you're saying that, perhaps, there could be a receptacle somewhere, say behind the the couch, or somewhere obscure, that may work, even though it is in on that same circuit breaker? I don't think I quite follow. I thought if the circuit had no power, there really is no way to tell which one worked last and which one croaked first...is there?

I have no tools for this, but I am looking at grabbing a no contact voltage tester on my way home from work today. Any tips for tracing the wiring path from the circuit breaker panel through the house?

And to answer PJmax, no, there are no devices working on that circuit that I am aware of, but this afternoon when I have daylight again I'm going to go around, maybe with a lamp or something, and one by one check every receptacle, etc.

 

Save your money, they aren't for troubleshooting.

 

Receptacles are typically wired A to B to C etc. One pair of the wires are incoming power and the other are outgoing power. If the connection at the device has failed on the connection at the outgoing pair there will be complete circuit downstream.

Normally wiring would start closest to the panel and move toward the far end of the circuit. Mostly and Easter Egg hunt. If you find a receptacle with only one pair of wires it is the end of the circuit.

An analog multimeter would be better than a non-contact detector. A non-contact can signal power but will not tell you if the neutral connection has been lost.

 

Ok I can get a multimeter - that's fine. I'll read the manual, etc, but could you give me a quick rundown on the standard procedure for testing these one by one?
Instinct says shut the power off, but then it's impossible to really measure current, so I should ask about that. Also, if I've got black/white/ground wires, which two do I connect the leads/clips to (or touch with the prongs)?
Finally, what result on the multimeter scale would indicate a failure in that particular switch/fixture/outlet, and similarly, what result on the multimeter would indicate that particular switch/fixture/outlet is performing normally?

 

And to add context to my question, I'm hoping I can do at least these basic diagnostics myself before bringing in an electrician. I will, if needed, but funds are tight. If this is a simple 'hook the red lead to this wire, and the black one to this wire, and it should say X, there's your problem" and then I just replace that switch or reconnect the wiring, that saves me and my family a lot of money. Also, I prefer not dying, so tips are helpful

 

You will be testing voltage not the device. Se the meter to nearest scale to 250 or above. You should see readings about mid scale. Disconnect the cables at a receptacle. One cable should be hot: Measure:

• Black to white
• Black to ground
• White to ground

You should get ~120 volts black to white and black to ground.0v ground to white.

The test can also be done with the receptacle in place by measuring:

• Wide slot to narrow slot
• Narrow slot to ground
• Wide slot to ground.

You should get ~120v wide to narrow and narrow to ground. 0v wide to ground

 

That's great info! How does that translate to testing light switches and fixtures? Receptacles sound straightforward (I do it with power ON right?)

 

Nothing indicates switches and fixtures need to be tested. Only maybe the connections in the boxes but receptacles first.

 

Okay my understanding from a previous post was that I should test everything on the same circuit, which includes fixtures and switches. Disregard that for now and start with the nearest outlet to the breaker panel and work my way away from it?

 

Yes that is the plan of action. We tripped up in explaining things to you. When we say "switches" or "lights" we are talking about the connections in the boxes.

 

Gotcha. Lick fingers, insert in outlets one by one until one of them doesn't shock me. Will keep you all posted.

 

But remember the problem could be in the last one that bit you.

 

a no contact voltage tester is GREAT for troubleshooting allways check it on a known hot wire first

if it keeps me off of a hot wire...................it is a great tool

it will not read very good over old cloth covered wire...........works on K&T

works good over pve covered wire and the new wire

it does not tell you if the white or ground is good

a 3 light outlet tester would tell you if you have a hot but no white

if it says you have reverser poliarity...you probably have a loose white connection some where......could be in a ceiling light box.....could be in a switch box

you need both testers

Mods Note: If you use a non contact tester or even a plug-in tester we won't have accurate enough information to help you.

 

No, no, no! But it is a good as a quick check before doing real testing .No, what he needs is an analog multimeter. We have chased more then one wild goose on this forum because we didn't know they were using a non contact tester and we thought the wire was hot when it really wasn't.

 

A non contact voltage tester is a great piece of test equipment. It was created for one purpose and one purpose only..... to show the presence of a hazardous voltage.

An actual test meter needs to be used for diagnostic purposes.

 

A non contact will only show if half the circuit exists and that is the drawback. It cannot detect an open neutral which is very limiting when troubleshooting.

 

My plan was to do this all yesterday but something more urgent came up. I'm going to grab a lower end non contact tester and an analog multimeter. The tester is more just something I want to feel a bit safer before I cram my hands into the box.

I'm going to go ahead and get a multimeter for the test described below, but I still feel a bit safer having the non contact tester nearby.

 

A non contact tester is a good idea as long as it is only for safety. Your plan sounds fine. Be sure to get analog not digital*. A cheap $8-#15 one is all you.

*Except for a couple of high end expensive digital meters digitals do not have the circuits to reject ghost voltages. The analog with its low impedance does it naturally.

 

Ok SO I'm going to throw a giant kink into all of your theories. First, a confession. I've been too tied up in personal matters to attempt this fix yet. I just haven't had the time.
We had some company visiting, and they were sleeping in the guest room, which is adjacent to the room without power. While, everyone wanted wifi and stuff back on, which WAS plugged into the living room. I grabbed an extension cord, plugged the power bar that has the computer and wifi router plugged into it and plugged it in around the corner in the bedroom. Found one more receptacle that is out. Odd, but it made sense because it was literally on the opposite side of the wall from one I knew was bad.
So I ran the cord further into the the room, and bam, the power works on the computer. We have wifi. The army of women is happy and life goes on. Meanwhile, nothing else has changed.
So to sum up...
-we unplugged a power bar from one wall with no power, then plugged it back in to an extension cord and then in another room. No other changes were made.

Today I go downstairs to change the laundry over and my son comes down and goes "look dad the lights work!". Sure as hell, everything is "normal again". I haven't plugged the computer back in properly yet, but we plugged the tv back in and it was fine.

Not sure if it's noteworthy but we did have a thunderstorm last night.

Really I don't have a clue - I did nothing that should have fixed the problem, but it's fixed.

 

It is not fixed, it is just now working. The problem needs to be found before it gets worse or potentially causes a fire. You have confirmed that there is a loose connection. Loose connections cause heat. Heat can cause fires.

Concentrate on the two formerly dead receptacle or the one just upstream.