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I noticed a very hot connection after wire brushing a rusty conduit clamp connector located at my water meter. It only seems hot when drawing current, as i have been remodeling this house and am not using much power. After turning off the dehumidifier that was running the connection cooled off. I then proceeded to clean up the area using my shop vac for 10 minutes and it once again got extremely hot. I am thinking the rusty connector is failing and i was hoping that if i replace it, the heat issue will be resolved. Also I have not located my ground rod outside of the house.


The dehumidifier was plugged into an outlet for the wash machine, which is a dedicated breaker labeled washer in the panel. When I was running the shop vac I was plugged in top an outlet that is on a different breaker labeled basement lights. My thought is a bad connection wher the rusty connector meets the conduit. Thinking of replacing the rusty connector if it is safe to work with

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    Uh oh! Something's causing current to flow at that bonding connection...can you try turning off breakers one at a time and seeing which circuit is to blame? – ThreePhaseEel Jun 10 '17 at 3:26
  • The dehumidifier was plugged into an outlet for the wash machine, which is dedicated only for the washer. And the outlet i was using my shop vac – Bil Jun 10 '17 at 3:36
  • is this a ground wire that goes outside? we need more info other than that it may be rusty. – joe Jun 10 '17 at 3:50
  • The ground wire is inside the house running through some thinwall over to the water meter where it is fastened to the copper water service line just below the meter. – Bil Jun 10 '17 at 4:00
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    Your rusty clamp that you cleaned is not the problem - you cleaned it , now it reveals a serious problem - Current through a ground wire ..we assume it is a ground - see my answer with added questions etc.. – Ken Jun 10 '17 at 6:11
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You have a lost neutral. Turn everything off NOW!

Your electricity is served to you as two "legs" with 240V across them -- and a center-tap called "neutral". This gives you 120V between a leg and neutral.

Water heaters and A/C units take the 240V directly and ignore the neutral. Any 120V load, however, connects between a hot leg and neutral to give it only half the voltage - 120V.

If something goes wrong with the neutral, crazy stuff happens. Each 240V leg has several 120V loads between the leg and neutral. If the neutral is lost, nothing "pegs" those voltages at 120V anymore! They are still 240V apart, and the two legs will add up to 240, but they could be 90 and 150 volts. (those unequal voltages, adding up to 240V, is the sure sign of this, if you have a voltmeter.)

That will start fires. So why hasn't it?

Neutral is called that because it's also bonded to the water pipe/ground inside your main panel. The intent is emergency use only. The transformer on the pole, also bonds its neutral terminal to a grounding rod at the base of the pole. Current is using this path instead (via dirt) because your neutral wire is broken. This problem will get much worse.

Dirt is not a reliable conductor, and if the resistance goes up, or your load goes up, your voltages could start getting wobbly and start blowing things up. That's why you need to fix it right away.

Also, this current flowing through your water pipe is corroding it. Normally no current should flow through the ground. It shouldn't be getting warm.

A lost neutral is a power outage, call it and report it as such! The problem might be inside your service panel, but they will probably tell you if it is.

Also, stay away from the clamp unless your main breaker is off. It is (wrongly) part of the electrical circuit, and if disconnected or messed with, it can shock you.

  • good write up to clarify the point and the seriousness of the ops REAL issue. His concern was the temperature of the connection after wire brushing - which only revealed to him his REAL issue. Neutral is missing. Good thing he noticed that and wrote in, it will be better for him to Check why he is missing that neutral, my suspicion is someone played in the panel at one point and disconnected his neutral or bonded the panel incorrectly. Of course if he has a power transformer on a pole could be some storm damaged something. Good write up. BTW : Electrocution (death) is possible not just shock. – Ken Jun 10 '17 at 20:35
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We are all speculating a bit because you have not provided enough details for us to have the same frame of vision as you do, and since there are no pictures it makes that hard with out the details.

You do not say where on Planet earth you are - so knowing what Voltage and the power system in your neck of the woods may be different. Here I assume you live in the USA and have a standard 120V/240V service.

To make sure we are on the same page as you and understand your situation...

'very hot connection ... after wire brushing a rusty conduit clamp connector located at my water meter'

We assume the very hot connection you are referring to is the rusty conduit clamp you wire brushed.

This indicates you fixed a bad connection and now you see a separate more serious issue - the connection is hot.

You did not cause that issue by cleaning the clamp connection, you just revealed the issue - like fixing dry wall and finding out there are termites in it. Changing the clamp will not resolve your issue (although it is not a bad thing when you fix the real issue.

A connection to your water meter, you state conduit clamp so lets clarify here what you have..

  1. Is your water meter electronic or is it mechanical ?
  2. Is your water meter a Mechanical type and the conduit clamp is connected to a water pipe ?
  3. Is your water meter an electronic type and the conduit clamp is connected to an electrical Conduit Pipe ?
  4. Please tell us where that wire on the clamp goes to, where is the other end of the wire connected ? We are assuming it is a ground wire .. but have no idea with what you have provided. Does it go to your panel or a grounding rod ??
  5. When was the home built ?
  6. Was the Electrical ever upgraded or are there sub panels in the house or outside like for a garage ?

The problem you have is that current is flowing through that (assuming it is a ground wire) ground wire! Which is Incorrect, changing the clamp will not fix the real issue electrically something is not correct.

This means that power is not flowing from Neutral Line to the Load. It can also mean that the line you have connected to that clamp is really your neutral ..

As one commenter said you should go through turning breakers off and verifying if it is one circuit or any circuit that causes this issue. Turn off all of them and then only your washer , if it gets hot maybe it is not wired correctly, turn it off and try a completely different one, not your basement lights..a different one than washer and basement lights and see if it occurs, if it does - I would venture it will for all circuits but can't be 100% sure without testing all of them.

Given you have plugged in to two different circuits (washer, basement lights) and see this same condition I am leaning towards your panel not being wired correctly. Depends on where that other end of the wire goes to ..

If all or any circuit causes this, check your Power - Line-In to the panel, You probably have 4 Wires , L1, L2, Neutral and Ground. Check the panel bonding, make sure none of your neutrals is tied to the grounding or vice versa grounding to the Neutral.

Be very careful inside the electrical panel, if you are not you can get Electrocuted as opposed to shocked. IE 6 feet under as opposed to a new hair do..

PS: Older homes may have some sneaky things done to pass a quick inspection, if it was a rental at anytime (for example neutrals used as grounds in an outlet) - look for this.

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