I am an apprentice electrician. I only have 1 1/2 years experience in new residential contruction. I live with my parents. They have a problem. Lights flicker and sometimes power is lost to some things but not others. No circuit breakers are ever tripped. The power comes on to whatever is affected usually within 10-15 minutes. More than one circuit is affected by this. I replaced their old Zinsco circuit breaker box because I've read that this could be a source of the problem and sice I've read where they are a fire hazard anyway so I thought it would be the first place to start. Although the house is old and has the main breaker located outside the house. I did not replace that. Any ideas where to start? Undervoltage problem from the power company?

As you've replaced the distribution panel, the next guess would be the main, or the utility transformer connections. It helps if you can get a meter on it when it happens.

Dave

Do you happen to have a couple 120VAC and 1, 240VAC cube relays lying around? You could hook the coils L1-N, L2-N, & L1-L2, via the 'a' contacts. Use #12 and wire on the load side of breakers for safety. Jumper the 'a' contact of each relay to seal it in and walk away. Indicating relays would add style points. Losing a 120VAC and the 240VAC relay means your losing a leg. Just a 120 relay dropping would clue you in to the nasty floating neutral.
Joe

Sinec you have flickering i would say there is a loose connection on that circuit. You need to take out all of the devices from the each box and check the connections. I bet you that one of the connections is burnt or almost there.

Loose connection.

It is good that you have replaced the ZINSCO, but for future i would not start out by replacing the panel.

I would start by checking your voltage at the panel. Check one leg to ground (120), then the other to ground (120), and finally both to each other (240). Then check each individual circuit breaker. If all that checks out, then I would locate the branch circuit that's giving u the problem and shut that breaker off. Only then would I start removing devices to check for good terminations. Probably a stab-lock somewhere, lol.

Thanks Tiger, joe, niko.

Niko, I have intermittent flickering lights and loss of power on more than one circuit. Replacing the box was something I wanted to do anyway so I figured I would start there.

Any other thoughts anyone?

Hello Chris,
I would borrow a multi-meter from someone at work and take some voltage readings. If the lights flicker so often, wait around for it to go crazy and take some meter readings. Since you said the problem is on multiple circuits, I would pull the cover off the outside main and meter pan. Check for water damage or corrosion on the equipment. Sometimes water gets into old services and makes a muck of everything. And last, make sure you have a good nuetral and that you have good ground connections, via the electrode and water main. You could have a bad nuetral somewhere. These are just a fews things you can check. Some of the guys will have some other good recommendations also.

Brian

Multiple circuits indicate to me that it is a main power supply issue. Service, Main Panel or Sub panel if present.

I had a customer some years ago with the same issue. After several visits I had no idea what the problem was.
The customer made a comment that "it seems to happen on windy days".
So I went back and visually inspected the incoming power from the service all the way back to the transformer. While standing under the XFMR I heard a cracking sound. (electrical) short.
Called POCO and they found that the service wires on the secondary had worn enough for them to short to each other intermitantley.

Moral of the story. "It's not always your problem, it could be theirs"

If the customer would not have mentioned windy days, this would still be happening. Go outside and have a good look around. But don't touch anything you are not trained to work on......Good Luck

Maybe your parents are screwing with you :-)

Are you sure they are physicaly on two different circuits?

I just want to make sure, because some people call receptacles and lighting two different circuits even though they are one.

I just want to make sure that we all are on the same page.

If you can get a hold of a meter that has recording capability. (Max, Min, Average) hook it up at the suspect circuit, turn on a resistive load (hair dryer) inside the house and see the voltage reading on the meter. If you have a large voltage drop at the output of breaker then move the meter to the bus bar, if you still have large voltage drop then call POCO.

Now, if you don't have large voltage drop at the breaker but have flickering lights inside the house (with your hair dryer on) then the problem is inside.

I am suggesting a hair dryer because it is large load and you want to put some strain on that circuit in order to create loose connection or flickering effect on that circuit.

Thanks everyone for your ideas. I'm going to wait until it happens aganin and start by checking the panel box (on the inside of the house) and the main breaker (on the outside of the house). Seems to me if I have a drop in voltage on one of the legs coming in to the main from the power company then it's the power companies problem. If I have a drop in voltage somehwere else in the main or the panel well then I can work backwords to find the problem.

Niko...yes I'm absolutely positive it's more than 1 circuit. The electric stove goes out, the washer but not the dryer, the furnace goes out, part of 1 bathroom, and one of the upstairs bedrooms. IT SEEMS LIKE IT IS ROUGHLY HALF THE HOUSE! The other half is fine.

What I don't understand, and maybe you guys can help me with this. I don't understand how this is possible? Can anyone explain how this could be?

Hi Chris,
Have you checked the Neutral busbar in the panel?
It sounds like there may be a couple of loose connections.
With a lot of calls to places with flickering lights and what-not, it's always been the screws holding the neutral wires into the busbar that have been to blame.
This problem really needs to be looked at in any case, a bad connection in any electrical system can be a potential fire waiting to happen.

Hi Trumpy. Yep I'm gonna check all that stuff as soon as it happens again. The lights don't hardly ever flicker however. The flickering usually precedes the power going off to roughly half the house. It also tends to usually happen at the same time of the day....early morning is when it usually happens when everyone is sleeping. It lasts usually about 10-15 minutes.

I don't think it could be loose screws as I have changed the panel recently and the problem did not go away.

I've got my multi meter laying out and the cover to the panel box off so I can quickly check everything as soon as it occurs. Usually it happens 2-3 times a week so I don't think it will be too long before I have more information.

But can anyone tell me how power to only half the house could go out? I would think it would be everything or nothing?

I want to try to rule out everything in the house before we call the power company.

If you lose one of the two legs feeding a subpanel then any circuit attached to that leg will de-energize but the circuits on the other leg remain energized.
I wouldn't rule out an iffy main breaker or whatever breaker is feeding your subpanel. I've had many calls where one leg of the breaker feeding a sub was intermittently or completely open. You can probably turn on lights on one of the effected circuits and go out and wiggle the breaker and see, or have someone see, if the lights flicker.

We get calls for this quite frequently, and 90% of the time it's where the poco splices to the mains coming into the service. A couple of simple questions usually will point me to a poco problem:
1. When does it happen? (eg. At dinner time when the stove is on, dishwasher is on drawing water from electric tank, and laundry is being done - all big loads)
2. What is affected? (more than one circuit, but all on same phase)

Check the poco splices at the house - from a distance you will often see that one leg has been overheated.

Twice I have found this in the meter pan, loose connection at the lugs.

This thread has been bothering some folks. Let me explain why.

An apprentice with 1 1/2 years of experience would have been mainly bending pipe, pulling wire, etc. If he's lucky, he might install some receptacles. He would not be doing service changes, or trouble shooting. Especially with a problem like this one.

An apprentice has his instructors and employer to ask for advice. Most I've known would like a problem like this to show off their skills.

The OP has not drawn on those resources. I have to wonder why. In the meantime, he needs to recognize that this is beyond his competence - and get some help. ECN is great, but we're not there.

I disagree. Chris21 chose to draw on ECN's resources, and we were there. Many in here like to show off their skills, and it's no different than any other troubleshooting questions that get posted in ECN.

An apprentice with 1.5 years of residential experience should have an understanding of how a basic household distribution system works, the hazards involved, and his limitations. My post was an opportunity for him to use some simple troubleshooting techniques without even picking up a tool. I can't see any harm in that.

It also depends on the apprentice. One does not have to follow the pace of the apprentice one might want to advance faster by asking questions and trying to better him/herself.
I don't see any problem with that and certainly there is no problem by asking someone with more experience.

My 2 cents.

First, I'd like to tell Chris21 welcome and that I commend his determination. He is in the right place to learn. This isn't meant to demean you in any way, nor downplay your experience. That you came here for help is good.

That said:
There hasn't been a single word of warning or safety in any of the replies. At 1-1/2 yrs of "apprenticeship" (whatever that may mean), doing only new residential construction, Chris may have never worked on anything that's even been energized before.
He may not HAVE an instructor to fall back on. His boss may have never done any troubleshooting at all; PA has no State licensing requirement, educational requirements, or exams.

The replies have suggested that he do everything from visual checks, which are great, installing octal base relays, to pulling the cover off of the meter pan and main while energized. (How about a frozen meter clip breaking off in his face to screw up his day?). These without a single warning, nor mention of safety equipment.

ECN has a good track record of responsibility and not suggesting unsafe practices. That record should remain intact.

Chris21, please stick around, ask more questions, and learn all of the things that we can teach you. You are the kind of guy that can probably benefit the most from the experiences that we have had. That's what we're about.

Sorry, I should have mentioned safety in my reply. Chris, I would tell you safety, safety, safety. Even experienced people can make a mistake or have a bad day. Dont mess with meter pan unless there is someone with experience with you, like a friend from work. If you are not comfortable doing something while trying to identify and learn from this problem, do not perform it. Think about what you are about to do and what you are doing when you do it. And last, make sure you have TPI (Two person intergrity) when working on or near energized equipment. You do not want to get hurt by yourself when no one is home.

My take is that someone who has told me of doing a panel swap, has already had his share of chances to assume room temperature. I figure that he must already know not to let those metal thingys touch those other deadly do-dads. But even experienced electricians might not think of using commonly available relays as about the cheapest, although crude, event recorder for a problem that might rarely manifest itself.

Years ago, a friend of mine was the CE of a 10 KW stereo FM co-located with the 2MW UHF transmitter that I maintained. He installed relays, indicators, and reset buttons on his 3 phase 480 input power. I had never given it any thought prior but realized that it was a clever idea. After that, I would walk back to his area after resetting a power outage on my transmitter. Seeing one of his phase lamps out would mean that I had to look no further for the source of my outage. Such a simple concept yet it saved a lot of time.

So Chris, I also want to welcome you to ECN! Measure twice cut once! Don't cut the pink one! Clear the airspace above you before opening or the runway in front of you before landing. Watch out for Pit Bulls with mood swings and most of all, never date women who REAAAAAALLY liked "Fatal Attraction"! There are centuries of combined experience on this board and much to be gained from frequent visits so read on, take care and be safe.
Joe

Figured out what the problem is. I took some meter reading as soon as the power went out. I found one of the legs coming into my main breaker (which is on the outside of the house) goes dead. In other words it's the power companies problem. So I called them and they are coming out to fix the problem. The thing that threw me was that I simply didn't fully understand how a panel box works. I never realized each leg powers roughly half the circuits. Pretty stupid. But once I understood that I turned out to be pretty easy to figure out.

Since I'm so inexperienced I'm just gonna lurk on the board for awhile and just read what you guys are talking about.

I LEARNED A LOT FROM YOU GUYS! THANK YOU ALL SO MUCH! I hope someday I can return the favor!

Chris, why don't you drop into the chat room some evening? It's not all technical discussion ... and a great place to pick the minds of folks with experience slightly different from yours! PoCo, AHJ, EE, even a REAL rocket scientist sometimes drop in.
Check it an evening ... you might get lucky!

OTHERWISE.....

Joe, one of the most dangerous times to be an apprentice is to be at the start of the second year. Guys at that point THINK they're 'almost electricians,' that they just need to put in their time and they're done.

This is in stark contrast to the same guys when they're near the end of the apprenticeship; by then, they've had their eyes opened to just how large a field electric work is .... and how only now can they really 'start learning.'

Chris, come on in here tonight. Heck, I'm not even an apprentice yet (only 15 Y.O) and am a regular visitor on Friday-Sundays.

Ian A.

Chris,
Congratulations on your successful troubleshooting! But please don't just be a lurker. This place has been a little slow lately. I have to imagine that some of the postings have brought follow-up questions into your mind. Please don't hesitate to ask that follow-up question.

Reno, what you say makes perfect sense to me. But Chris, by the very way he presented himself to us, makes me think that he seeks information before acting. The ones that think they know everything probably don't spend much time here.
Joe

This could not be any more true. Some of the guys in my class at school do not try to learn anymore than what they have to to pass a test. They have no real interest in this trade, other than a paycheck, and their work in the field shows it.

The school gets together with the contractors and sends out "progress" reports. One guy had his come with a very low score and said he worked as a 2nd year apprentice. Funny thing is we just finished our fourth year of school. Shows he still has a ways to go.