Puzzled about fuse box voltages
#1
Member
Thread Starter
Join Date: Mar 2017
Location: usa
Posts: 16
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Puzzled about fuse box voltages
Ok I have a general switch fuse box. One side has 140v and 100v on the other. This only happens when major appliances are turned on. This meaning furnace microwave etc. But when only lights is on its 120v at main and outlets. On 1 leg I get power to neutral and power when checked with volt meter.
#6
Member
Join Date: Feb 2016
Location: United States, Virginia
Posts: 1,705
Received 273 Upvotes
on
230 Posts
Sounds to me you have a loose or bad neutral. That will show up when there's a heavier load than just lights.
Make sure the meter is set to voltage high enough to measure 300V and test across the two legs (red and black). It doesn't matter to which legs you place the red and black test leads to.
Make sure the meter is set to voltage high enough to measure 300V and test across the two legs (red and black). It doesn't matter to which legs you place the red and black test leads to.
#10
Checking the neutral is done by inspecting the neutral connections not using a multimeter. Once you confirm ~240 volts you will need to call the electric company emergency number and ask them to check the connections on their side.
Edit: Your voltage is good. Call the electric company now.
Edit: Your voltage is good. Call the electric company now.
#11
Member
Join Date: Feb 2016
Location: United States, Virginia
Posts: 1,705
Received 273 Upvotes
on
230 Posts
With 247V you should have a fairly even split between the two legs to neutral, 124V/123V or close to that. If one leg is low and one high such as 147V/100V then you have a service neutral problem and need to have it fixed.
#16
Do you have an aerial (overhead) service ?
The problem is most likely at the service head.
Turn off any valuable electronic equipment because it's in danger if it's on the high voltage side.
The problem here is not that the two legs are changing voltage because they are not. What is changing is your neutral is no longer at 0 volts.
The problem is most likely at the service head.
Turn off any valuable electronic equipment because it's in danger if it's on the high voltage side.
The problem here is not that the two legs are changing voltage because they are not. What is changing is your neutral is no longer at 0 volts.
#18
Member
Join Date: Feb 2016
Location: United States, Virginia
Posts: 1,705
Received 273 Upvotes
on
230 Posts
I had to deal with this same problem recently. I had voltage of about 100/145 and lights would flicker when any heavy load would kick on. I had a bad aluminum underground cable where the insulation got nicked during install and the wire turned to mush.
#20
Call the power company emergency number.
Usually the power company is responsible up to the meter pan.
Usually the power company is responsible up to the meter pan.
#25
Member
Thread Starter
Join Date: Mar 2017
Location: usa
Posts: 16
Upvotes: 0
Received 0 Upvotes
on
0 Posts
This place was made in 1970 with original box. It has the box on the pole from the main. Then a buried wire to another box with 2 plugs, then to my inside panel box. So I have 3 panel boxes after meter. yes the citys is a drop in line.
#31
Member
Join Date: Feb 2016
Location: United States, Virginia
Posts: 1,705
Received 273 Upvotes
on
230 Posts
At the first disconnect after the meter check the voltage between the legs and neutral. Checking the total voltage at 240 doesn't tell you a thing. You need to see if there's an imbalance between the two legs and neutral.
#33
Member
Join Date: Feb 2016
Location: United States, Virginia
Posts: 1,705
Received 273 Upvotes
on
230 Posts
You need to be methodical in your testing. Test the voltage on each leg to neutral on the load side from the meter before the first main fuse/breaker, then test the same way after the first main fuse/breaker. Move to the next connection/panel point and do the same until you find where the voltages are imbalanced. You need to figure out the first point where the voltages between the legs to neutral are greatly different.
#34
To check amps you need a clamp on meter, but that is not your issue. You have a loose neutral.
At the pole box check between each hot to neutral. They should both be something around 120 volts. If it is not correct there then it will be on the power companies side and you need to call Otter Tail power's emergency number and tell then you have a loose neutral. It was extremely windy Monday and Tuesday (50 - 60mph gusts) so it wouldn't surprise me that some connections came loose.
At the pole box check between each hot to neutral. They should both be something around 120 volts. If it is not correct there then it will be on the power companies side and you need to call Otter Tail power's emergency number and tell then you have a loose neutral. It was extremely windy Monday and Tuesday (50 - 60mph gusts) so it wouldn't surprise me that some connections came loose.
#35
Just a quick update: I reached out to Nicholas by PMing him as he lives in MN. Communicating with him I found out he has a pole mounted meter (overhead) with a main fuse pullout below. This is a rural setting with a mobile home on the property. From the main on the pole it goes underground to a panel near the mobile home with two 50 amp receptacles on it. The mobile plugs into one (of two) 50 amp receptacles which feeds a panel inside the mobile home. Each receptacle has its own 40 am fuse block.
The issue lies in the MH panel. He sent me a picture and the neutrals are burned and corroded. He is going to install a new neutral bar for now and possibility a new panel at a later date.
I just wanted to make sure you guys get the info as I always like to know the outcomes as much as, I would assume, you do.
The issue lies in the MH panel. He sent me a picture and the neutrals are burned and corroded. He is going to install a new neutral bar for now and possibility a new panel at a later date.
I just wanted to make sure you guys get the info as I always like to know the outcomes as much as, I would assume, you do.