fbestelectric
Member
- Location
- Braxton, Mississippi
At the community center in the town where I live, they have had a problem with lights flickering and have asked me to come and check it out for them. The system is 102/240 single phase.
What I have discovered on the flickering of the lights is that they have 150 volts going to them and then it drops to 130 volts so flickering was not the problem, but a voltage spike causing the lights to brighten and then dim. One leg to neutral I was getting 150 volts and the other leg 100 volts.
Thinking there was a problem coming from the power company I checked voltage on the line side of the meter with the meter pulled and was getting 250 volts phase to phase and 124 volts phase to neutral.
The building was built in 1970 and they have had jackleg electricians over the years doing work there, so I went back inside cut all breakers off and then cut one breaker on at a time trying to isolate the problem. What I discovered is that when anyone of the breakers was cut on, the voltage would go down to 100 volts on one leg and 150 volts up on the other leg for all breakers.
System was not grounded so I drove a ground rod and grounded the incoming neutral at the meter, no change. There are six fluorescent fixtures on one breaker so I used this a guinea pig and went to each fixture to see if where was a problem by removing one at a time, but there was no change when I cut the breaker back on. At this time I am puzzleheaded and not sure what the problem is. I was turning back on all the breakers that I had turned off and one breaker in particular that was for the refrigerator was turned on and a light that was already on brightened up giving me the 150 volts on the phase. I am not thinking there is a problem with the refrigerator, but I am thinking that the neutral coming from the power company is lose at the weather head or at the transformer where when checking voltage under no load I am getting good voltage readings, but when under a load is when there is a problem.
Has anyone ever experienced this problem before?
What I have discovered on the flickering of the lights is that they have 150 volts going to them and then it drops to 130 volts so flickering was not the problem, but a voltage spike causing the lights to brighten and then dim. One leg to neutral I was getting 150 volts and the other leg 100 volts.
Thinking there was a problem coming from the power company I checked voltage on the line side of the meter with the meter pulled and was getting 250 volts phase to phase and 124 volts phase to neutral.
The building was built in 1970 and they have had jackleg electricians over the years doing work there, so I went back inside cut all breakers off and then cut one breaker on at a time trying to isolate the problem. What I discovered is that when anyone of the breakers was cut on, the voltage would go down to 100 volts on one leg and 150 volts up on the other leg for all breakers.
System was not grounded so I drove a ground rod and grounded the incoming neutral at the meter, no change. There are six fluorescent fixtures on one breaker so I used this a guinea pig and went to each fixture to see if where was a problem by removing one at a time, but there was no change when I cut the breaker back on. At this time I am puzzleheaded and not sure what the problem is. I was turning back on all the breakers that I had turned off and one breaker in particular that was for the refrigerator was turned on and a light that was already on brightened up giving me the 150 volts on the phase. I am not thinking there is a problem with the refrigerator, but I am thinking that the neutral coming from the power company is lose at the weather head or at the transformer where when checking voltage under no load I am getting good voltage readings, but when under a load is when there is a problem.
Has anyone ever experienced this problem before?
