We were on a service call today and the women said that her TV and other electronics kept getting destroyed by overloads. She said the electric co. had allready been out and checked their side of the service. The women then asked if "we could check all her neutrals out" and see why her electronics kept getting destroyed. She said she thought the romex in her trailer walls had been stapled to tightlly and were causing the problem. She also said her surge protector strips were not protecting any TVs or electronics. So what where would you have started on this service call? I meen you cant very well slip in the walls and look at each romex staple.
Check my neutral?
- Thread starter mrhanky
- Start date
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brian john
Senior Member
- Location
- Leesburg, VA
Re: Check my neutral?
Sounds like she has an open or intermittently opened neutral. If this effects all circuits, (she is losing equipment all over the house) it is in the service disconnect or panel, or meter can.
If it is on particular circuits check that circuit all devices.
Of course it could be in both places!
An open neutral in the panel will but 240 across the branch circuit loads. Assuming the loads do not have identical impedances, the voltage drop across one item will be different that another. This OVERVOLTAGE will damage the equipment.
Sounds like she has an open or intermittently opened neutral. If this effects all circuits, (she is losing equipment all over the house) it is in the service disconnect or panel, or meter can.
If it is on particular circuits check that circuit all devices.
Of course it could be in both places!
An open neutral in the panel will but 240 across the branch circuit loads. Assuming the loads do not have identical impedances, the voltage drop across one item will be different that another. This OVERVOLTAGE will damage the equipment.
pierre
Senior Member
- Location
- Westchester County, New York
Re: Check my neutral?
Adding to what Brian has said. Look in the panel for a three wire circuit. It may be feeding most of her electronics seeing as this is a trailer home. If you do not find the problem there, it might be in the boxes where the receptacles are spliced downstream of the panel.
Good Luck!
Pierre
Adding to what Brian has said. Look in the panel for a three wire circuit. It may be feeding most of her electronics seeing as this is a trailer home. If you do not find the problem there, it might be in the boxes where the receptacles are spliced downstream of the panel.
Good Luck!
Pierre
Re: Check my neutral?
Another thing, is the trailor fairly new ? If so call the manufacutre they have drawings of all their trailors, this will tell/show you where the junctions boxes are without tearing the place apart. Those trailors can be a real nightmare trying to find the hows and whys anything was done, and if this problem has reared its ugly head before and MAY have a ready solution.
WmColt
Another thing, is the trailor fairly new ? If so call the manufacutre they have drawings of all their trailors, this will tell/show you where the junctions boxes are without tearing the place apart. Those trailors can be a real nightmare trying to find the hows and whys anything was done, and if this problem has reared its ugly head before and MAY have a ready solution.
WmColt
cselectric
Senior Member
- Location
- Wisconsin
Re: Check my neutral?
Does this installation happen to be in a cold climate? Maybe it's a long shot, but I have seen this once before in Northern IL. What we found was a problem with the neutral in the meter can. The meter was configured as a bottom feed with the neutral lug directly above the incoming pipe. In that configuration, the neutral was brought straight into the lug from the pipe (wound up being about 3" of cable in the cabinet, no bends or loops.) Anyway, the movement of the conductors caused by frost heave had worked the neutral loose in the lug, causing the same problem you describe.
Does this installation happen to be in a cold climate? Maybe it's a long shot, but I have seen this once before in Northern IL. What we found was a problem with the neutral in the meter can. The meter was configured as a bottom feed with the neutral lug directly above the incoming pipe. In that configuration, the neutral was brought straight into the lug from the pipe (wound up being about 3" of cable in the cabinet, no bends or loops.) Anyway, the movement of the conductors caused by frost heave had worked the neutral loose in the lug, causing the same problem you describe.
jrdsg
Senior Member
- Location
- Vancouver, Canada
Re: Check my neutral?
cselectric that is one informed reply...
cselectric that is one informed reply...
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
Re: Check my neutral?
Following on CSElectric's comment,
I had a service call to a trailer two weeks ago. . .lights fluttering from time to time. . .as far as the owner / occupant could tell, the flutter was throughout the trailer, but he was more fixated on the cable TV converter boxes (2) that had failed and the window AC that no longer worked and he assured me that the trailer park had sent out a guy that said there was no problem with the pedestal.
I advised immediate disconnect of the service until I got there.
When I got into the troubleshooting, I found two Wadsworth 120/240 circuit breaker panels in excellent condition, the cords from the pedestal were intact and tight.
The voltage swings were measureable in the meter base line side. . .
The local PoCo had ownership of the underground lateral supplying the pedestal, and when they arrived, they took responsibility for the failure in their buried neutral. . .
I never did hear exactly what happened to compromise the buried neutral.
Point is, the neutral will fail on the line side of the Point-Of-Attachment from time to time as well.
Al
[ August 25, 2003, 01:12 PM: Message edited by: al hildenbrand ]
Following on CSElectric's comment,
I had a service call to a trailer two weeks ago. . .lights fluttering from time to time. . .as far as the owner / occupant could tell, the flutter was throughout the trailer, but he was more fixated on the cable TV converter boxes (2) that had failed and the window AC that no longer worked and he assured me that the trailer park had sent out a guy that said there was no problem with the pedestal.
I advised immediate disconnect of the service until I got there.
When I got into the troubleshooting, I found two Wadsworth 120/240 circuit breaker panels in excellent condition, the cords from the pedestal were intact and tight.
The voltage swings were measureable in the meter base line side. . .
The local PoCo had ownership of the underground lateral supplying the pedestal, and when they arrived, they took responsibility for the failure in their buried neutral. . .
I never did hear exactly what happened to compromise the buried neutral.
Point is, the neutral will fail on the line side of the Point-Of-Attachment from time to time as well.
Al
[ August 25, 2003, 01:12 PM: Message edited by: al hildenbrand ]
G
Guest
Guest
Re: Check my neutral?
I would check the voltage drop across each circuit breaker. It's easy to do. Put one end of your voltmeter on the lug and the other end on the load side of the circuit breaker. That will tell you the voltage drop through the breaker itself.
Put your temperature probe on the circuit breaker and see if it is overheating.
Then I would remove each breaker from the bus. Look for signs of burning, corrosion, or contamination. If the bus is bad replace the bus if you can get an identical bus. Otherwise you have to replace the whole panel.
Put your nose up to the breakers. If they emit a foul odor there is probably internal arcing and they need to be replaced.
Check for backstabbed (backwired; quickwired; speedwired) receptacles and switches. They are very prone to arcing with age.
Use a LINE CONDITIONER for electronic devices instead of surge suppressors. A good line conditioner is in the $300 to $400 range. You can get APC ones for about $100 but you get what you pay for:
600 watt Line-R APC line conditioner
1250 watt Line-R
[Note: This post spellchecked with ieSpell. Grammar not checked.] ieSpell
I would check the voltage drop across each circuit breaker. It's easy to do. Put one end of your voltmeter on the lug and the other end on the load side of the circuit breaker. That will tell you the voltage drop through the breaker itself.
Put your temperature probe on the circuit breaker and see if it is overheating.
Then I would remove each breaker from the bus. Look for signs of burning, corrosion, or contamination. If the bus is bad replace the bus if you can get an identical bus. Otherwise you have to replace the whole panel.
Put your nose up to the breakers. If they emit a foul odor there is probably internal arcing and they need to be replaced.
Check for backstabbed (backwired; quickwired; speedwired) receptacles and switches. They are very prone to arcing with age.
Use a LINE CONDITIONER for electronic devices instead of surge suppressors. A good line conditioner is in the $300 to $400 range. You can get APC ones for about $100 but you get what you pay for:
600 watt Line-R APC line conditioner
1250 watt Line-R
[Note: This post spellchecked with ieSpell. Grammar not checked.] ieSpell
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