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View Full Version : Strange happenings..


pelle
Oct 19, 2006, 01:46 PM
tkrussell,

This one is for you. I work for an electric and gas utility. One of my coworkers had the following occur.

1st
Went to a residence for another reason but the homeowner said when my phone rings my light comes on.. when it rings again it gets brighter.. so he tried and sure enough 1 ring on, 2nd brighter all the way to off at the fourth ring, 3 way bulb and it was a touch lite..

2nd
Then they said the blow about 40 - 50 bulbs a year throughout the hse. So he check voltages coming in OK.. connections in the meter channel and the breaker panel OK.. so he assumed a neutral problem.. took a voltage at the main good put on a heavy 120 load voltage stayed the same.. on the other side the voltage went UP 1 - 1.5 volts..
I have never seen this nor has he..

Any thoughts about this..

tkrussell
Oct 19, 2006, 02:03 PM
I would first check the grounding electrode system, and be sure the service, phone and CATV demarc's are grounded properly.

Second, connect a power recording at the incoming main to record that utility power does not fluctuate more than 2% imbalance between each 120 volt leg to ground. Let the recorder run at least 24-48 hours.

A loose or corroded neutral, or a loose ground bus to electrode connection, at the transformer/pole or at any utility to customer connection, can cause a broken neutral.

Also possible there is a loose connection in a shared neutral somewhere in the house wiring. Once a shared neutral in a multiwire circuit is broken, higher than normal voltages , up to 240 volts, can be impressed on one or more of those circuits.

As far as the inside lamps burning out, sure sounds like a broken neutral issue. The phone, not sure on that, but telephone grounds are many times done incorrectly, and are rarely checked.

pelle
Oct 20, 2006, 01:41 PM
More info.. we checked the handhole all connections good.. 1 other house off this handhole they have no problems.. I understand the neutral things.. bad neutral can cause 200 on 1 leg and 40 on the other when load is applied.. the question is do you know of any reasons the voltage would go up on 1 leg and remain the same on the other.. I think it was 120 121 no load.. then 122 and 121 on the other leg.. I would expect a net difference but not an increase..

Also our m&t dept is setting charts on the house..

tkrussell
Oct 20, 2006, 04:07 PM
The voltages seem fine, I believe the flucuations are due to difference in the impedance of the line and transformer.

Then the bulb burning should be caused by a loose neutrral in the house wiring.

If the charts show your standard +/- percent voltage average obligation is met,then the utility is fine and the house is suspect.