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	Subject - dimmed lights-lost nuetral dan7167 Hello this could be a long question so thank you in advance to anyone with the patience to read it.Here goes; This past Wednesday morning I recieved a call from a customer who told me that he was having problems with his lights,he descibed lights coming on dim,switches affecting lights they were not supposed to etc. This sounded to me as though he may have lost the nuetral and I suggested that he have the power company come out and check their connections (approx. 1 month ago he had called me with partial power and it turned out to be a bad splice on a hot leg at the pole . The service is underground no splices at the house). He called back shortly afterward and told me the power company had checked their end and found nothing wrong,good connections at pole,120-240 at meter etc.I then went to the customers home arriving at approx. 11 am (remember this).I had no sooner took the cover off his panel than everything suddenly returned to normal I checked all conections for tightness or burnt connections and found nothing wrong I then pulled the meter and checked that,again everything seemed fine.Due to the weather that we were having that day ,snow and sleet,I was of the opinion that the power company had overlooked something and that there was a bad connection at the pole.I called them back and they sent out a crew to remake their splices at the pole.I then left the house and everything was working normally.The following morning I got an early call from the customer and he told me that the problem was back.I went back to the house and again rechecked all connections which were fine. I shut off all breakers,but main main and put a meter on line side off the main and voltage was normal 120/240. I then asked the customer to go throuhout the house and unplug everything. As I started to turn on the breakers one at a time the voltage on one leg started to rise(at one point to 176v.)while the other leg seemed to drop. not all breakers caused any changes only about 6 in a 40 circuit panel. I then pulled meter again and with all breakers off remove line side nuetral from it's lug to ckeck street power again.no problem 120/240 to neutral.I returned to checking voltage while flipping breakers but could not seem to isolate the problem or discern a pattern.The time got to be about 11am and again everything suddenly returned to normal.I asked the customer if had had any timers in the house on anything and he said no.At that point I had to tell him that I had no idea what the problem was and that it could very likely happen again the following night.He asked me if I would mind if he called another electrician and I said no I would welcome someone elses insight.This morning his other electrician called me and said he was at the house and everything was working normaly.We talked and basicly he could'nt find anything wrong either.While I didn't directly ask the power company if they were having problems in the neighborhood I assume they might have mentioned it after the third call to the same adreess so I don't think the problem is on their end.Does anyone out there have any explanation for this? JimmyDee I would like to welcome you to the Electrical Knowledge site. The neutral is definitely opening up somewhere. I wonder if you took an amp probe and checked to see how much of the neutral current is flowing through the grounding electrode connection instead of the neutral conductor. I had a problem one time where the service took a hit of lighting and burned a conductor off in the service mast. Caused all sorts of problems. Its possible that there is a bad spot in the underground lateral run but not likely. Jim dan7167 Thank you for your response. no i did not try that,but now that you bring it up I am going to.If the problem is underground this could be a nightmare as it passes under a main road.But again thank you for your response. wilkie I thoroughly enjoyed reading your long post. The same thing happened to on of my techs last month. He spent hours chasing what everyone will agree sounds like a lost neutral. He even took the direction of turning everything off and trying to isolate the circuit/s causing the problem. His voltage topped 180 volts on one leg, and only several circuits affected the voltage. We found the problem was an underground service neutal was in the process of seperating. Under a small load, it would handle the flow. Once a significant load was applied ( which is probably what your 6 out of 40 circuits did) the neutral would seperate and then all the "ghosts" would return. After the utility fixes your problem, you may want to advise your customer to apply for reimbursement for your bill, and any related loss of equipment in the home. Our customer lost a big screen TV and a computer, both of which are being repaired by our local utility. lctrc789 You definitely have a nuetral problem when you have one leg increase in voltage that means the other one is dropping. Causing your dimming and perhaps even more damage on the high voltage coming in to effect here. John A. Peters I agree with the diagnosis that it is the neutral somewhere. Here in S.F. I have seen the power company check the voltages on both legs after hooking up a high wattage hair dryer to one phase using large alligator clips. Then he checked the other side. Has the problem been solved? That 11 o'clock clue is interesting. Maybe a neighbor has a hot tub on a timer or I don't know what, a kiln?