Your recent repair? 2013 - 2020

[homestead]

Our ground went bad at the transformer on the outside pole. Lineman said water
gets into the connection and freezes loosening the connection.

Our problem was the neutral line but it is tied to ground in the electrical box.

 

[ERD50]

I agree with others that a bad ground/neutral is the likely culprit. However, I find it astounding that you've blown three TVs, and continue to use this as is!

This is also a safety concern. Shut it down until it is fixed!

Seriously.


-ERD50

 

[imoldernu]

I agree with others that a bad ground/neutral is the likely culprit. However, I find it astounding that you've blown three TVs, and continue to use this as is!

This is also a safety concern. Shut it down until it is fixed!

Seriously.


-ERD50

Yeah... done.

 

[NW-Bound]

People often use the term "neutral" and "ground" interchangeably, and that adds to the confusion. I will try to explain the problem that imoldernu experienced, but without a diagram to point to, it may be a bit difficult.

Of the 3 conductors in the Romex wire, the "ground" wire is not supposed to carry any current, or the GFI (ground fault interrupter) if installed would shut down that circuit. Current is supposed to flow only between the "hot" and "neutral" wires.

Electricity is brought into the home from the streetside transformer via 3 wires: two "hot" wires, and a "neutral". The neutral wire is grounded at the transformer or electric pole, and then again at the electric meter at the home. Usually, this is done by connection to a ground rod. See diagram below (linked from http://hyperphysics.phy-astr.gsu.edu/hbase/hph.html).

The voltage between each of the hot wires and the neutral is 115V. The voltage between the two hot wires is 230V, as they are opposite in phase, meaning when one swings positive in the sinewave cycle, the other goes negative, and vice versa. High-consumption appliances such as water heaters, cloth dryers, stoves, A/C, etc... draw 230V from the two hot wires. Electric outlets and lighting fixtures draw from one of the two hot wires and the neutral, and the load is intentionally distributed between the two hot wires by wiring some circuits on one hot wire, and some on the other hot wire.

If the neutral wire connection to the power company transformer is broken or intermittent, what will happen?

If there are two appliances, one sitting between hot wire #1 and neutral, and the other sitting between hot wire #2 and neutral, what will happen is the following. Current will flow from the hot wire #1 through appliance #1, then to the neutral wire (which is now disconnected from the streetside transformer), then to appliance #2, then to hot wire #2. The effect is exactly the same as if you wire the two appliances in series, then power them with 230V.

If the two appliances are identical, such as two 100W bulbs, they act as a voltage divider, and each will share 1/2 of the 230V. However, if one has a higher consumption than the other, it behaves as a lower resistance, and the voltage divider is no longer balanced. The device with the lower resistance will have a lower voltage across it, and the device with the higher resistance will have a higher voltage than 115V.

In the case of Imoldenu, I think the neutral connection is intermittent, and that caused the TV to blow up as it draws a lot less current than the electric heater that is sitting on the other hot wire.


PS. The bad or intermittent connection of the neutral wire may be at the meter or even at the transformer, in other words anywhere along the path from the streetside transformer into the power panel box.

 

[aja8888]

^^^ Good diagram and explanation of the function of the neutral wire as a lot of people do not understand this..

 

[Chuckanut]

Your recent repair?

I was told that with AC the idea of a hot and neutral wire was not really true. Any comment?

 

[NW-Bound]

Most house A/C are large units that run off 230V, meaning off the two hot wires. So, the A/C wiring does not need a neutral wire, as that is used only when you need 115V. The A/C wiring still has the ground wire, which is used to ground the metal enclosure of the unit.

The reason for the ground wire is for connection to the metal enclosure of any appliance or device. If there is a fault causing a current leakage to the enclosure that may be touched by the user, the attached ground wire will divert that current and saves the user from electrocution. The ground wire is therefore not to be used for normal operation of the device, meaning it is not to be used for the function of the neutral wire if the latter is needed.

PS. And because the ground wire is used only to shunt off any leakage current and not to carry the normal operating current, it is usually of a smaller gauge, and not insulated.

 

[meierlde]

Thanks...
Question... Where is the ground? At the outside box? How and where to check this, and locate the problem? I had the feeling that the man I spoke with thought it could be a major project to identify. I read somewhere that the ground wire at a plug could be loose, and cause problems.

If you have a multi meter read the voltage on the plugs. If a 3 wire outlet test both the hot -neutral and hot- ground connections (you should get about the same voltage). If you have the trailer you might measure the voltages there also. It is possible that the wire between the main box and the inside box has become disconnected. Note that in general ground should run to the main box.

 

[ls99]

Most house A/C are large units that run off 230V, meaning off the two hot wires. So, the A/C wiring does not need a neutral wire, as that is used only when you need 115V. The A/C wiring still has the ground wire, which is used to ground the metal enclosure of the unit.

The reason for the ground wire is for connection to the metal enclosure of any appliance or device. If there is a fault causing a current leakage to the enclosure that may be touched by the user, the attached ground wire will divert that current and saves the user from electrocution. The ground wire is therefore not to be used for normal operation of the device, meaning it is not to be used for the function of the neutral wire if the latter is needed.

PS. And because the ground wire is used only to shunt off any leakage current and not to carry the normal operating current, it is usually of a smaller gauge, and not insulated.

Minor correction. Even 220 air conditioners need the neutral plus the ground wire of course. The relays are 110. As are the fan motors.

 

[imoldernu]

In the case of Imoldenu, I think the neutral connection is intermittent, and that caused the TV to blow up as it draws a lot less current than the electric heater that is sitting on the other hot wire.

Many thanks for an excellent explanation. I had to read it through three times, but now I understand what is probably happening. I didn't originally talk about this, but I tried dozens of different combinations of appliances, lights, different on/off breaker box switches, as well as unplugging a separate 220V connection at the main that wasn't used any longer. Every time, every change... it looked as if the problem was solved. Now I see that the relative resistance probably allowed a time period before blowing the circuit... I hadn't allowed time to build up enough resistance to trip the breaker.

So now, will be knowledgeable about the problem... The handymen who service our campground are pretty good, but most learned all the trades, and aren't sharp enough to know "how" and learn by trial and error. The only really good electrician retired two years ago, and most of my neighbors shrugged, when asked to recommend a good one.

Thanks to all for your input... am convinced this website beats the all the fixit sites on the web.

 

[imoldernu]

It is possible that the wire between the main box and the inside box has become disconnected. Note that in general ground should run to the main box.

That may be a possibility. I looked at the bare ground wire that attaches to the inside breaker. It connects to the metal frame of the trailer. I don't know if there is another wire that goes to the main outside box. I'll be there when the "electrician" is working... just in case he's as confused as I was.

 

[travelover]

That may be a possibility. I looked at the bare ground wire that attaches to the inside breaker. It connects to the metal frame of the trailer. I don't know if there is another wire that goes to the main outside box. I'll be there when the "electrician" is working... just in case he's as confused as I was.

I think that you will find that one of the neutral wires that run to your separate circuits is loose inside the box. That's why you only have a problem with one or two outlets. The bare ground wire is there for protection against electrical shock. Under normal conditions it does not carry current.

See all those white wires connected in the upper part of this box? One of those was not properly tightened.

 

[NW-Bound]

Minor correction. Even 220 air conditioners need the neutral plus the ground wire of course. The relays are 110. As are the fan motors.

My 5-ton A/C runs on 208/230 V only. The compressor as well as the fan motors are 230V. The relays are 24V, and fed off a transformer which also powers the thermostat. But other arrangements exist, I am sure.

I do not think my house wiring for the A/C has that neutral wire (I have poked around the predecessor A/C in this home quite a bit). Perhaps I should go look. You make me wonder about my oft-claimed "superior" memory. Darn, I hate old age.

 

[NW-Bound]

I have to go and look to see if my house A/C wiring has that neutral wire. And the result is ... my memory remains "superior"!

Apparently, the wiring standard may have changed over the years, and with copper being so expensive nowadays, new A/Cs all run off 230V to save on wiring costs.

But back to imoldernu's problem, in order for the loss of the neutral connection to cause the two outlets on two separate hot wires to cross-couple, the two outlets must have their neutral connected. If a circuit has its neutral connection loose at the box, that circuit will simply be intermittent.

So, I wonder if the house was wired wrongly in the 1st place. A way this can happen is if an outlet is wired with its neutral connection made to the neutral wire of another circuit. Again, each circuit must have its own neutral wire going all the way back to the box. Sharing a neutral wire between two hot wires can cause the problem like imoldernu observes.

 

[ls99]

Interesting. My 15 yo 1 ton AC has 220VAC compressor, 110VAC fan and contactor for switching. The furnace/AC indoor is all 110VAC with 24VAC controls.

SO far works fine. One of these summers it will crap out.

 

[tryan]

More fun with electricity ... my cleaner said the stove didn't work at the lake. The light worked but no burners. Had vacationers coming for the weekend so I grabbed a new one at the Depot threw it on my utility trailer and drove up expecting to replace the stove.

After unplugging the old and plugging in the new ... same result ... no burners. On closer examination of the outlet ... it was warped and COOKED. Killed the breaker opened the outlet. The red hot wire was melted. Apparently the connection was loose allowing it to arc. The arcing melted the box and wire. Easy fix once identified (new box; pulled a couple inches of new wire up ... thankfully there was some slack).

DW always hated the stove so I left the new one in place and will move the "old" to another unit when needed.

 

[Ronstar]

Some more fun with electricity. Just took out some can lights and replaced them with low voltage pendants. Had to tear into the ceiling to rewire, add a transformer and wiring, and patch the holes. I need to replace a defective fixture, add a low voltage dimmer for a magnetic transformer and then I'm done

 

[imoldernu]

I have to go and look to see if my house A/C wiring has that neutral wire. And the result is ... my memory remains "superior"!

Apparently, the wiring standard may have changed over the years, and with copper being so expensive nowadays, new A/Cs all run off 230V to save on wiring costs.

But back to imoldernu's problem, in order for the loss of the neutral connection to cause the two outlets on two separate hot wires to cross-couple, the two outlets must have their neutral connected. If a circuit has its neutral connection loose at the box, that circuit will simply be intermittent.

So, I wonder if the house was wired wrongly in the 1st place. A way this can happen is if an outlet is wired with its neutral connection made to the neutral wire of another circuit. Again, each circuit must have its own neutral wire going all the way back to the box. Sharing a neutral wire between two hot wires can cause the problem like imoldernu observes.

Mmmm... just as I thought this was getting easier, it got more complicateder.

The outside Main Box has two leads... one to the park model (inside main box) and a separate one to the add-a-room (no box inside). In the beginning, when the problem first occurred, the inside main box (main) switch tripped. In the few times after that when the problem happened, the shut down was always at that inside box. The circuit to the add-a-room always stayed on, and I could bypass the inside box with an extension to keep the refrigerator cold. I could never use any combination of plugs/electrical load, or use of different appliances including heaters to duplicate the problem after resetting the circuit breaker.

The last time I had the problem, the main (outside) box shut down, and I had to wait for a half hour for it to cool... So now, the problem becomes more complex.

I was hoping some kind of test could identify a particular place where the problem could be fixed. If not, then it would mean tearing apart each one of the individual wall plugs. There's a total of 22 of them in the trailer, and they are not all easily accessible. (The trailer is not like the inside of a house... The walls and skin are built around the electrical system, and there is no "play" in the wiring).

My frugal self sees me supporting the local "approved" electrician for the entire winter, as he experiments.

 

[bld999]

Mmmm... just as I thought this was getting easier, it got more complicateder.

The outside Main Box has two leads... one to the park model (inside main box) and a separate one to the add-a-room (no box inside). In the beginning, when the problem first occurred, the inside main box (main) switch tripped. In the few times after that when the problem happened, the shut down was always at that insidebox. The circuit to the add-a-room always stayed on, and I could bypass the inside box with an extension to keep the refrigerator cold. I could never use any combination of plugs/electrical load, or use of different appliances including heaters to duplicate the problem after resetting the circuit breaker.

The last time I had the problem, the main (outside) box shut down, and I had to wait for a half hour for it to cool... So now, the problem becomes more complex.

I was hoping some kind of test could identify a particular place where the problem could be fixed. If not, then it would mean tearing apart each one of the individual wall plugs. There's a total of 22 of them in the trailer, and they are not all easily accessible. (The trailer is not like the inside of a house... The walls and skin are built around the electrical system, and there is no "play" in the wiring).

My frugal self sees me supporting the local "approved" electrician for the entire winter, as he experiments.

How big is this main breaker that tripped? 100 amp or bigger? If a main panel is getting so hot you have to wait to reset, I would get a capable electrician to troubleshoot and repair asap, before the whole place goes up in smoke...just imho.

 

[sengsational]

Some more fun with electricity. Just took out some can lights and replaced them with low voltage pendants. Had to tear into the ceiling to rewire, add a transformer and wiring, and patch the holes. I need to replace a defective fixture, add a low voltage dimmer for a magnetic transformer and then I'm done

Very nice! Brave to cut into ceiling drywall...getting that flat again can be a challenge.

 

[ERD50]

Mmmm... just as I thought this was getting easier, it got more complicateder.

....

My frugal self sees me supporting the local "approved" electrician for the entire winter, as he experiments.

imoldernu, this shouldn't be complicated. From all signs, you have a bad neutral or ground connection. I highly recommend a licensed electrician, not some handy man who is going to 'experiment'. Cough up the bucks, this isn't an area to apply false economy - how many appliances are you going to blow up, plus risk fire and shock hazard? A loose neutral can cause parts of an appliance that would normally be at zero volts to reach 110V - that is a potentially lethal shock hazard.

A licensed electrician will (OK, 'should') go through a logical procedure to find the fault. It should not involve experimenting, just measuring, and then repairing.


edit/add: I see I cross posted with bld999, well, it isn't just his opinion, it's mine too! I'll go so far to say it isn't opinion, it's fact!

-ERD50

 

[travelover]

Got extremely lucky today - twice. I entered the utility / store room to find a pipe leaking at the well / tank interface, but as luck would have it, the spray was onto a wall, then into a floor drain.

Generally, when these galvanized fittings leak, they are a rusted mess and I chase the leak from fitting to fitting as I try to replace the bad fitting, but disturb the other fittings. So, I went to Home Depot and bought one of every single fitting that made up this junction. To my amazement, the bad fittings just unscrewed and all I had to do was wrap them with Teflon take and resemble.

I think this calls for a beer.

 

[samclem]

I think this calls for a beer.

Beer? This calls for a drive to the Stop-N-Rob for purchase of a lotto ticket! These things come in threes, don't waste it!

Galvanized pipe--you know you're just buying time until the next disaster. A changeover to PEX would be a great wintertime project!

 

[travelover]

..........Galvanized pipe--you know you're just buying time until the next disaster. A changeover to PEX would be a great wintertime project!

Yea, but......it is a one inch line with a T fitting, a ball valve and a connection to a 3/4" copper line. I'm not sure how to do that in PEX .

 

[samclem]

Yea, but......it is a one inch line with a T fitting, a ball valve and a connection to a 3/4" copper line. I'm not sure how to do that in PEX .

I'm no expert. If the rest of the internal pipes are copper, I'd probably just try to stick with copper as far back toward the well as I could go (dielectric union to the galvanized, with a good bridge for grounding assuming that the pipes serve as a ground right now).