Help! Flickering lights/haunted house

[farmer2009]

When turning things off remember that each leg alernates sides in the panel. It doesn't run straight down one side. This is how a double breaker gives 240.

 

[coobie]

When I was a troubleshooter (lineman) for the utility company we always put load on the "high side) of the (one phase at a time)customers meter cabinet. If the other phase spiked while the one we tested dropped, it was obviously a open nuetral. Their could be several reasons for that, bad URD cable, connection at pedestal or transformer, etc. If we saw no drop in voltage between phases it was usually on the customers side. Their was of course, some other more complicated rare examples that required more troubleshooting.
You need to put load on (microwave) each phase and test. Keep backing up from the main, to the meter, to the ped, risor pole, etc until you get balanced load, then You'll find your problem

I agree with this comment.I am also electric lineman.Make sure to check all of your grounds in your fuse panel to make sure they are tight also.With the main breaker OFF.Not all lineman trouble shooters are created equal,some are better than others.

 

[grsthegreat]

im betting its a corroded neutral in a direct buried line. their test connection should determine this by bypassing the underground. Ive run into similar situations in the past. the direct burial wires corrode but leave enough digested aluminum to complete the circuit...but cant handle loads.

 

[strum456]

When turning things off remember that each leg alernates sides in the panel. It doesn't run straight down one side. This is how a double breaker gives 240.

Good point. I should have mentioned that.

 

[zzvyb6]

What happens when you disconnect the main breaker and power your main panel with a 240v generator ?

Its either the house, or the panel, or from the meter to the pole. Pull the meter and do the same. If the problems go away, it's no longer in your hands.

 

[gocards1177]

I haven't logged in since lunchtime but I think I've done most of these suggestions. The main connections were already checked for looseness. I don't have a generator. Heres what I did:

First I turned on all of the lights and space heaters. I did all of the testing at the panel. 240 across the buses, but when tested separately to neutral one was 107, the other 131. Then I started turning off one breaker at a time until they were all off. Certain breakers with higher loads made bigger jumps, but even when all off, I was getting 119/121 at the bus bars. Then I turned everything back on except the 240 stuff, 111/128. Then turned off one side(every other breaker) and got 113/125, then did the opposite and got 112/127. I think the difference was loads. Then with everything on again I tested at the service cables going into the main breaker and got 107/131. Then shut everything off again and got 119/121 on both in/out of main breaker. The I tested service cables with main off and got 119/121. I didn't think to check against the new ground.

Here's my conclusions: I don't think it's any of the 240 appliances. I don't think it's any of the "secondary" wiring throughout the house. So I think I've traced it back to either the buried cable or the main breakers. I was at work when the electrician came by, but my wife says he didn't do the acrobatics I did and she doesn't remember him using a multimeter although maybe she just didn't see it. I guess I'll just wait until they run a temp cable on Wednesday and see what happens. Until then were down to necessary electronics only. Thanks and I appreciate everyone's input!

 

[gocards1177]

Grrrrr. I'm frustrated. This hadn't gotten anywhere. The electrician and utility company came out last Wednesday and realized they needed my underground cable located before they could temporarily bypass it. We called Monday to let them know the lines were marked and they said they'd come today. Then they called this morning to say they could so anything because the ground is frozen. So they're going to
Try again Friday but the weather forecast isn't much better. I called the electrician when I got home just now to discuss. I suggested no passing with a generator but he said unless I had a whole house generator it might not tell us anything. And he said that he's convinced it will be the underground cable and once that's replaced the bill is on me. Sheesh.

 

[gocards1177]

By the way. I have a kill-a-Watt meter hooked up in the kitchen and it was reading 98 volts at one point last night! We haven't used our computer in 2 weeks. If some appliances get ruined because of this...

 

[CobyRupert]

More like :

///////resistance/////////120V (Line-Neutral)) (L1) -----
// |
// |
// |
/////////// Nuetral/////Zero 0-Volts//////(Grounded/Earth) 240V (Line to Line)
// |
// |
// |
///////////resistance)////////120V (L-N)(L2) __|___

but then neutral connection, or it's bond with ground/earth goes bad, and the neutral is not pegged to O volts, thus the 240V L-L is not evenly divided in half to 2 phases of 120V (L-N), instead, now the 240V (L-L) is split across the two resistances, in proportion to one (L1) circuits resistance compared to the others (L2) circuits resistance. (Example if L1 resistance is twice the size of L2's, then the voltage will split 1/3 (60volts) in 1 circuit and 2/3 (180V) in the other.) The way the 240V L-L is split and the voltages measured in any one circuit will change as you switch different resistences (loads) in and out of the circuit, but always add to 240V. With a floating neutral , it now looks like this:

///////resistance (twice that of ckt. L2)/////////160V (Line-Neutral)) (L1) -----
// |
// |
// |
/////////// Nuetral///// -- Not connected to (Grounded/Earth, O Volts) 240V (Line to Line)
// |
// |
// |
///////////resistance)////////80V (L-N)(L2) -----

Edit: Grrrr. My vertical lines showing constant 240V between ckt L1 and L2 don't align.

 

[gocards1177]

More like : ///////resistance/////////120V (Line-Neutral)) (L1) ----- // | // | // | /////////// Nuetral/////Zero 0-Volts//////(Grounded/Earth) 240V (Line to Line) // | // | // | ///////////resistance)////////120V (L-N)(L2) __|___ but then neutral connection, or it's bond with ground/earth goes bad, and the neutral is not pegged to O volts, thus the 240V L-L is not evenly divided in half to 2 phases of 120V (L-N), instead, now the 240V (L-L) is split across the two resistances, in proportion to one (L1) circuits resistance compared to the others (L2) circuits resistance. (Example if L1 resistance is twice the size of L2's, then the voltage will split 1/3 (60volts) in 1 circuit and 2/3 (180V) in the other.) The way the 240V L-L is split and the voltages measured in any one circuit will change as you switch different resistences (loads) in and out of the circuit, but always add to 240V. With a floating neutral , it now looks like this: ///////resistance (twice that of ckt. L2)/////////160V (Line-Neutral)) (L1) ----- // | // | // | /////////// Nuetral///// -- Not connected to (Grounded/Earth, O Volts) 240V (Line to Line) // | // | // | ///////////resistance)////////80V (L-N)(L2) ----- Edit: Grrrr. My vertical lines showing constant 240V between ckt L1 and L2 don't align.

I think I follow you but in layman's terms do you think the most likely source of the faulty neutral is in my buried cable?

 

[CobyRupert]

Most likely in the neutral connection some where, either the connection at your box, in the cable, or at the utility's transformer. Note: Your panel neutral bus should be "grounded" to 0 Volts by a connection to your ground rods. This connection should be made at one location only, at the first disconnect point of your service. Typically there is a jumper between the panelboard's neutral bus (white wires) and the ground bus (green wires) in the panel, and the ground bus is connected to a ground rod in earth.

 

[gocards1177]

Most likely in the neutral connection some where, either the connection at your box, in the cable, or at the utility's transformer. Note: Your panel neutral bus should be "grounded" to 0 Volts by a connection to your ground rods. This connection should be made at one location only, at the first disconnect point of your service. Typically there is a jumper between the panelboard's neutral bus (white wires) and the ground bus (green wires) in the panel, and the ground bus is connected to a ground rod in earth. <img src="http://www.tractorbynet.com/forums/attachment.php?attachmentid=357821"/>

One of the first things the electrician tried was adding a new ground.

 

[grsthegreat]

i still say that once a temp run is placed above ground all your issues will disappear. Then the only thing left to do i start digging a new one. And DONT agree to direct burial. If they had pipe the 1st time this wouldnt even be an issue.

 

[gocards1177]

i still say that once a temp run is placed above ground all your issues will disappear. Then the only thing left to do i start digging a new one. And DONT agree to direct burial. If they had pipe the 1st time this wouldnt even be an issue.

yep. I'm with you.

 

[farmer2009]

i still say that once a temp run is placed above ground all your issues will disappear. Then the only thing left to do i start digging a new one. And DONT agree to direct burial. If they had pipe the 1st time this wouldnt even be an issue.

Around here power company will no longer use direct burial. But you have to provide the conduit.

 

[ultrarunner]

What size conduit are you looking at?

I know Comcast wanted a 2" conduit just to run a line to a single family home.

 

[gocards1177]

Around here power company will no longer use direct burial. But you have to provide the conduit.

Actually it's all on me. That's their policy for buried service lines. Bummer.

 

[grsthegreat]

Actually it's all on me. That's their policy for buried service lines. Bummer.

well that sucks. here, and in all the states I've worked at in the past, the utility companies have been responsible for all lines (buried & overhead) that go from the power generating system to the METER. Anything after the meter was the customers responsibility.

 

[mbohuntr]

Sounds like you may have it narrowed down, another way to check the panel box is to run your appliances and try to see a hot spot in the panel with a FLIR camera. A laser thermometer will work as well. You could also lift both ends of the service feed and megger it...

 

[gocards1177]

Temporary cable fixed it. Of course the utility company guy didn't come out until 230 on a Friday so they'll have to come back next week to fix it. Wait wait wait.