Voltage Drop In Mobile Home

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  #1  
Old 01-13-15, 02:10 PM
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Voltage Drop In Mobile Home

Hi guys, I just bought a '95 mobile home which I am working on fixing up.
I have some electrical experience mostly installing new wiring and fixtures.
There is an issue with the electrics in this mobile home, if I turn a light on and then turn a second light on the first light goes dim, this happens to lights all over the mobile home, both the main lights and lamps plugged into the receptacles. I need to fix this can anyone tell me what I need to look for ?
 

Last edited by ray2047; 02-13-15 at 01:43 AM. Reason: Change Title At Request Of O/P.
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Old 01-13-15, 02:49 PM
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How does power come to the mobile home? Do you have a breaker box on a pole that feeds a a breaker box in the MH? If so what is the breaker size at the pole that feeds the MH. What size and type of cable is used. Do any of the connections look corroded? Do you have a multimeter preferably analog? Do you have a clamp on amp meter?
 
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Old 01-13-15, 02:55 PM
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The dimming happens with just a couple light bulbs turned on? No other major electric?
 
  #4  
Old 01-13-15, 06:37 PM
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Yes, the place is empty so no other electric being used, I had the power turned on and went by yesterday evening to check it and found the problem with the lights so I turned the power back off at the 200 amp main breaker. I plan to go back there at the weekend and try to find the cause of this electrical fault.
 

Last edited by ScareCrow2000; 01-13-15 at 06:59 PM.
  #5  
Old 01-13-15, 06:56 PM
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The power comes in at a pole outside there is a box on the pole with a 200 amp breaker and two 20 amp breakers. I think the two 20 amp breakers are for outside power receptacles, there is one on the pole below the box.
Inside the mobile home is a regular board with several breakers. There is no obvious corrosion at the main box outside, the breakers operate smoothly, the same is true of the breakers inside. Yes I do have an analog multimeter
 
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Old 02-12-15, 10:54 PM
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Moderator please change the title of this thread to Voltage drop in mobile home"

Well I still haven't identified the cause of this voltage drop, I have only managed to spend a few hours though because I have been tied up with something else.
I have a question i hope someone can help me with. My electrical experience is almost all from England 240 volt residential wiring so I am not entirely familiar with the American way of doing things.
For example in England we usually put lighting on a separate breaker from the outlets, when we wire the lights we usually use the loop in ceiling method and make off the connection in the ceiling as per this diagram typical_wiring_of_a_loop_system_ceiling_rose_big_zpsc014a73c.gif gif by lyngarth | Photobucket
I have noticed when i switch the light on and off a floor lamp plugged into an outlet flickers, so I am thinking the connection must be made in the switch, in other words the switch instead of at the light fixture and the switch itself is interfering with the entire curcuit is this normal in the US ?
 
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Old 02-13-15, 02:08 AM
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Here are the two most common ways in the U.S.

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Here is a couple of variations. "Load" could be another receptacle or lighting circuit.

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Note: While national code requires a white wire used as a "hot" (ungrounded conductor) to be remarked some color other then white, gray, or green it almost never is remarked.

Note: Mobile homes fall under Department of Transportation rules not NEC or local building codes and wiring can be strange.
 

Last edited by ray2047; 02-13-15 at 02:53 AM.
  #8  
Old 02-13-15, 05:57 AM
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My electrical experience is almost all from England 240 volt residential wiring so I am not entirely familiar with the American way of doing things.
The American way for house wiring generally has three wires bringing power to the home. There are two "hot" lines with 240 volts between them. There is a "neutral" that is tied to ground (earth) (using a lot of rules) where hot to neutral is 120 volts for both hots.

In the home, individual circuits for lighting, small appliances, electronics, etc. consist of one hot and the neutral. There might also be larger appliances using 240 votls only via the two hot lines or using both 120 and 240 volts with all 3 lines in a cable going to the receptacle for that appliance. One kind of circuit that causes a lot of confusion in the U.S. has all three wires for 120/240 volts but all of the usage is by 120 volt equipment with lights and receptacles each connected to the neutral and one of the hots. (This latter circuit is called a multiwire branch circuit.)

Typically a circuit from one breaker in the panel daisy chains from one receptacle box or switch box to the next. Less common is having the circuit cable from the panel go to a junction box (usually in the ceiling) where cables branch off from there to the various receptacles, etc. There is no firm rule about whether all the receptacles and lights in one room are served by the same circuit. There are some rules whereby certain circuits may serve only certain receptacles or only one room such as a laundry room.

You probably have loose connections here and there in the home wiring. Note that loose connections in the neutral path can result in abnormal voltages both below and above 120 volts that will fry electronic equipment.

Try more tests, using four or more fixtures with incandescent lamp plugged into different receptacles (wall plugs). Turn different fixtures on and off and observe what happens to the others..
 

Last edited by ray2047; 02-13-15 at 08:16 AM. Reason: Formatting - add quotes
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Old 02-13-15, 06:59 PM
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Thanks for the info guys when I am going to the mobile home tomorrow morning I'm going to do a thorough check of all the wiring.
I think the third picture probably represents the way the lights are wired into the circuit although that would not explain why operating the light switch, momentarily interrupts the power to the rest of the circuit and causes the floor lamp to momentarily flicker off and on. I am going to pull a switch and its box tomorrow to see if there are pigtails or not. The last picture represents the way we usually do it in England.
The last time I was there I did a couple of quick tests first i checked all the receptacles with a 3 light quick tester but it didn't detect any faults. (I'm not if sure they really do what they say they do, I never used one of those except to check outlets after I wired them myself)
Then I did some voltage checks with my multimeter on the bedroom circuit which contains several receptacles including the bathroom RCD, two lights in the bathroom and one light in the bedroom.
This was the result.
Circuit no load 120v
Circuit one bedroom floor lamp on 115v
Circuit one bathroom light on 85v
Circuit both bathroom lights on 70v
 
  #10  
Old 02-14-15, 06:20 AM
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There appears to be a loose connection somewhere in the wiring, anywhjere from the utility pole transformer to where the floor lamp wiring branches off from the bathroom wiring.

Possibly in the box where the bathroom light switch is. A wire nut (marrette) could be loose. Wires going into the switch could be loose.

Possibly in the breaker box. One of the breakers, not ruling out the main breaker, could be loose where it fits onto the fins behind it.

Take the cover off of the light switch box. Press on the yoke (metal strip) holding the switch in place. Do lights dim or voltages change?

A common cause of loose connections is in the switch (or receptacle) itself when the wire is pushed into a hole in back and is supposed to stay in place without a clamp screwed down from the outside. The side screw terminals are more reliable, although each time you pull something out of a box, recheck to be sure the screws are tight.

If other circuits show the full 120 volts while the bathroom/bedroom circuit shows 70-85 volts then we rule out the wiring from the utility pole to the breaker panel and we rule out the breaker panel itself for having the problem except for the bathroom/bedroom individual circuit breaker.

Try to keep your tests brief and with juyst the floor lamp on pulling the voltage down to 115 volts. Prolonged operation at 85 volts will cause the loose connection wherever it is to get hotter faster.

If two wires want to go under one screw, cut a short length (pigtail) of the same color and use a wire nut to connect that as shown in the third diagram above.
 

Last edited by AllanJ; 02-14-15 at 06:46 AM.
  #11  
Old 02-14-15, 06:55 AM
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i checked all the receptacles with a 3 light quick tester but it didn't detect any faults. (I'm not if sure they really do what they say they do,
They don't. Often they indicate a wiring problem but not the correct problem.
 
  #12  
Old 02-14-15, 06:58 AM
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You are kind of chasing your tail, you need to start at the beginning.

Start where the power comes into the property at the pole. Check the large wires with your meter set to 240 volts or higher. You should get 240 volts between the two hots, and 120 volt from each hot to neutral. Also do the same check on the breaker that is feeding the wires to the MH. Do this check with all other breakers off in the panel.

If that all checks out, go to the main panel in the MH. Again, do the same checks and also check between hot(s) to ground. Do this check with all other breakers off in the panel. Then turn on just the single pole breakers and check them. You should have 120 volts to neutral. You can then check any two pole breakers in the panel. you should have 240 volts between hot to hot.

I suspect you have an open hot someplace and you are back feeding through some 240 volt appliance such as a water heater.
 
  #13  
Old 02-19-15, 11:32 AM
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Hey guys thanks for all the info and suggestions, I actually printed out this thread and took it with me, I managed to spend an hour after work testing voltages before it got dark yesterday.
I didn't test voltage outside at the pole because of the weather but I will do that either this evening or tomorrow.
I tested the voltages at the breaker panel with my analogue meter.

Hot to Hot 237volts
Left hot to neutral 115volts
Right hot to neutral 120volts
So one of the hots is 5 volts low is that normal ?
Hots to ground gave the exact same voltages.

I then checked the voltages at each breaker to neutral, I made this diagram to show the voltages.
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After I did all that I turned two breakers on, the top right 15amp and the 3rd right 15 amp. These are the bedroom/bath I tested last week and the living room.
So I tested the voltage at one of the living room outlets.
Living Room no load: 115v
Living room one floor lamp on in living room: 100v
Living room, One Bathroom light on: 135volts
Living room, Two bathroom lights on: 175volts

So it appears the living room circuit has a similar problem, the voltage drops when in use, but now I also find when the bed/bath circuit is in use which also has the voltage drop, there is a corresponding voltage rise in the living room circuit.
All the other breakers in the panel were turned off during this last voltage test.
 

Last edited by ScareCrow2000; 02-19-15 at 11:49 AM.
  #14  
Old 02-19-15, 12:10 PM
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You have a problem with the neutral wiring. Most likely the problem is outside the home, in the large wires going to the meter and on up to the utility pole.

But we don't have quite enough information to prove that beyond doubt.

Repairs to the wiring upstream past the meter need to have you call the electric company

Do the wires from the bed/bath breaker and the living room breaker exit the panel through separate cables or conduits or bundles?

Meanwhile you should take the opportunity now to tighten up all of the screws and set screws holding the smaller wires in the breaker panel. Do not use tremendous force. If a screw seems tight, loosen it a quarter turn and then tighten. This cleans off the connection for better current flow.

Flip off each breaker before tightening the screw(s) on it.

Leave the big lugs holding the fat wires for someone with lots of experience to tighten up.
 
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Old 02-19-15, 12:14 PM
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Living room, One Bathroom light on: 135volts
Living room, Two bathroom lights on: 175volts
That indicates a bad neutral. We need that pole reading.
 
  #16  
Old 02-19-15, 02:05 PM
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Your voltages will appear normal until a load is imposed on the hot. Then it will swing up or down. A space heater works well a a heavy load.
 
  #17  
Old 03-21-15, 10:49 AM
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I have been tied up with another project but last week I swung by there to try something different.
I pulled all the breakers off the panel except one single pole breaker and turned it on,I plugged in a couple of lamps and checked the voltage, it dropped as usual to about about 75 volts.
I then went to the breaker panel and checked the voltage on both the 120 legs, one was reading 75 volts the other was reading 155 volts. I do not understand that. How can the voltage on the other pole be affected and rise when no breakers are on it ? I unplugged the lamps and both legs in the panel read about 120 volts.
I figured this must be a problem at the pole outside so i called the power company, they came out and checked it and told me everything is fine on their end.
I called a couple of electricians they were pretty vague they suggested a loose neutral but when I asked them how can the voltage on both legs be affected when only one of them has a breaker attached they couldn't really say. So I am still at square one with this.
 
  #18  
Old 03-21-15, 11:24 AM
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The voltages on both legs ARE NOT being affected. You are measuring them both to a neutral wire that is not staying at 0 volts. If you notice the legs always add up to around 240v because you always have that. When you measure to a floating neutral it only looks like the legs are different voltages.

Ok.... the power company said your drop is ok. If they measured it with a voltmeter only and you had nothing connected in the house it may show as ok.

It appears you don't have a solid ground to your service.

Do you have a ground rod..... if so.... it may have a problem ?
Is your main breaker inside the house in the panel or outside ?
Do you have a cold water ground or a metal water service ?



Can you shoot us a pic of the inside of your panel ? http://www.doityourself.com/forum/el...rt-images.html
 
  #19  
Old 03-22-15, 11:05 PM
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PJmax: Here is a picture of the panel I apologize for the quality, I took it the other day with my phone not intending to upload it.
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I see what you mean about the neutral not staying at zero, that had not occurred to me.
In answer to your questions I have a ground rod it is under the mobile home but I do not know how well it is connected I will have to check it.
The main 200 amp breaker is in the panel outside at the pole together with two twenty amp breakers.
I don't know if I have cold water ground I will have to check, what should I look for ?
In the UK where I am from the ground and neutral are completely separate at the home, I don't really understand the US grounded neutral system but I tested for continuity between ground and neutral at the panel inside the home, there is full continuity, I believe that is correct ?
I am very confused about this, it contradicts everything I thought I knew about residential electrics, I thought we have power coming in and the reason it flows through the circuits in the home is because it is drawn to the neutral that is at zero volts, so if the neutral is disconnected somewhere there is no power, yet people keep saying this might be caused by a disconnected neutral this makes no sense to me what am I missing ?
I test between hots and neutral, hots and ground at the panel, no load voltage is 120 that means there is the correct difference between the hots and both ground and neutral therefore one or both of them have to be correctly connected right ? So when it is under load what is changing?
I thought I would try a new test next time I go there, my idea is to disconnect everything from the panel in the home except the incoming hots and the neutral. Then using a length of romex I will create a temporary circuit right there on the floor with a couple of outlets, and connect it to one of the single pole breakers and see what happens. If it works correctly I will know there is no problem with the incoming neutral and vice versa if it doesn't work correctly. I will wait for your reply before I do this if you would let me know what you think I would be very grateful or if you have a better idea let me know.
 

Last edited by ScareCrow2000; 03-22-15 at 11:49 PM.
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Old 03-22-15, 11:32 PM
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I can't see much detail in your panel picture. I can't see a neutral or ground bar. I think I see the neutral hiding but I don't see any grounds coming into the panel which is not correct.

If you have a panel outside then that is your main panel. If I'm not mistaken the ground rod should go to that panel. The panel inside is considered a sub panel and there should be four wires there.... two hots, a neutral and a ground from the main panel. I don't see a ground coming in the service conduit.

In theory.... the power company is supposed to deliver 120/240v to your house. Their neutral is supposed to be at 0 volts. I've seen it a lot higher than that. When I do or work on a service I always check the neutral. Normally the grounds at your service will keep that neutral at 0v unless you don't have the proper grounds.

Can you get into your main panel outside ? There is where you should start your testing. Put a load on a circuit in the house and then go out and check it in the main panel. See if the inbalance shows out there. Check and see what you have for grounds and where they are connected. Look for corrosion in that panel.

A picture of the service panel would be helpful too.

If you can't find a problem..... leave the load connected to your panel and have the power company come back again to recheck their lines.
 
  #21  
Old 04-24-15, 12:11 PM
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I have had so many other projects going on this mobile home has been on the back burner but I went out there again yesterday and gave everything a closer inspection.
At the panel there was a connection, the white went to one breaker, the black went to another breaker and the ground went to the neutral bus, I found the other end of that cable laying under the mobile home and not connected to anything I don't know whether that was really having an effect related to my issue but I disconnected it from the panel anyway.
Also under the mobile home I discovered the three main 4 gauge cables are joined with black tape around the joints. and the ground from the panel is connected to the steel frame under the trailer.
I have a question about that ground. The power is shut off at the main panel at the power pole in the yard. I tested for continuity between the ground and neutral at the panel inside the home, they are connected is this correct ?
I am now thinking there is an open hot somewhere, and because the neutral and grounds are connected it is feeding back into the neutral, is that a reasonable assumption ?
 
  #22  
Old 04-25-15, 05:35 AM
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"deleted .........................................
 

Last edited by AllanJ; 04-25-15 at 05:51 AM.
  #23  
Old 04-25-15, 05:58 AM
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Continuity or lack of continuity between ground (earth) and neutral proves nothing and gives no useful information for this topic.

To help narrow down on where the neutral problem is, do the following:

Repeat your tests with different incandescent lights turned on. Measure hot to hot and also both hot to neutral voltages at the box on the pole outside and also at your primary inside panel using the lugs where the fat (#4) feed wires are attached.
 

Last edited by AllanJ; 04-25-15 at 06:18 AM.
  #24  
Old 04-25-15, 06:30 AM
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"At the panel there was a connection, the white went to one breaker, the black went to another breaker and the ground went to the neutral bus, I found the other end of that cable laying under the mobile home and not connected to anything."

This cable has nothing to do with the problem. Just being connected does not affect the circuit. Something has to be connected/plugged in and turned on and drawing power to affect the circuit or the system voltage.

A 2 conductor cable may be used for a 240 volt only circuit (such as for a water heater or welding machine) by having both the black and white wires connected to breakers. The white wire should have been marked with a band of black tape or stain at both ends.
 
  #25  
Old 04-25-15, 09:35 AM
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Also under the mobile home I discovered the three main 4 gauge cables are joined with black tape around the joints
There should not be exposed joints under the motorhome. By exposed I mean not in a junction box.

There's a good chance the neutral splice there is bad. You don't have a hot wire issue.

Technically.... neutral and ground will measure the same because for all intents and purposes they are the same and are connected together, or should be, at one point.
 
  #26  
Old 04-25-15, 10:21 AM
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I discovered the three main 4 gauge cables are joined with black tape around the joints
(Not cables wires.) You need to shut off main power, remove the tape and see what was used to connect the wires together. They should not just be twisted together.


Wire: An individual conductor.
Cable: two or more conductors in a metallic or non metallic sheath.
 
  #27  
Old 04-26-15, 08:44 PM
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OK I went back out there today. Cutting the grass took most of my time but I had to get that done it was getting waist high, so then I did the voltage tests at the main panel on the power pole outside.
The voltage is good at the main panel, both poles stay at 120v when lamps are turned on inside.
The next thing I did was to disconnect all the neutrals at the inside panel except one and turned off all the breakers except the one for the bedroom circuit that still had a neutral connected.
I turned the power on at the main panel.
I turned on the main light in that room it functioned correctly I then plugged a lamp into an outlet, at first the lamp flickered like crazy and I could hear a sound from the breaker panel I flipped the breaker off and on and it settled down I checked the voltage in the panel both hots were normal 120v
I said aha now we're getting somewhere.
So then I took each neutral that I had disconnected and touched it to the neutral bus on the panel the first few I touched had no effect but then one of them caused the lamp to flicker like crazy again and it went off as did the main light but the breaker had remained on the whole time.
I then realized the breaker was stuck it was trying to trip but was unable to, this was causing the lamp to flicker like crazy.
By this time it was getting dark, I was tired from fighting half an acre of waist high weeds with a lawnmower and my experiments with the panel had blown all my light bulbs bulbs so I decided to call it a day.
Tomorrow I am going back armed with some new breakers and bulbs.
 
  #28  
Old 04-26-15, 08:59 PM
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We don't seem to be getting anywhere here.

If a breaker was trying to trip and it didn't, it would explode or the wire would burn.
All the neutrals from all the circuits should be connected to the neutral bar. Connecting them one at a time is not telling you or helping you in troubleshooting your problem.

Take the breakers out of the panel and check the buss bar where the breakers lock on......
Is there any corrosion ? (don't touch the buss bars with the main breaker outside turned on)

Breakers should not be making any noise but you could here a sizzling sound if the breaker wasn't making a solid connection to the buss bars.
 
  #29  
Old 04-27-15, 06:54 AM
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Do not unhook neutrals while the hot wires for those cables or circuits are still connected.

Depending on what is plugged in or wired to and switched on for the affected circuits, unhooking neutrals will cause more abnormal voltages and seesawing than you had before.

By the way, if there is no significant load on any circuits then neutral problems will not show up.

Bring a hair dryer, a metal baking pan, and several table lamp fixtures or floor lamp fixtures and a supply of incandescent light bulbs of at least 60 watts. For tests you should start with at least 100 watts of light plugged in at each test location.

When you see a problem and need to go out and measure voltages at the outdoor panel, put the hair dryer in the metal pan, hopefully not turned all the way up, before leaving it unattended.

Measurements are just as good if the light is noticeably dim compared with very dim. If you find that a light bulb has burned out when you come back insdie after making a voltage measurement, then that measurement should be considered invalid and should be discarded with the test being repeated.

(You could use an iron instead of a hair dryer, but some irons cycle on and off when on low settings. This can confuse you when you go out and make measurements and see nothing abnormal outside because at that moment the iron has cycled off, and when you come inside the iron has cycled on and the problem returned.)
 

Last edited by AllanJ; 04-27-15 at 07:15 AM.
  #30  
Old 04-27-15, 10:28 AM
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AllanJ
Do not unhook neutrals while the hot wires for those cables or circuits are still connected. Depending on what is plugged in or wired to and switched on for the affected circuits, unhooking neutrals will cause more abnormal voltages and seesawing than you had before.
With each breaker switched off and each neutral disconnected those circuits are dead right ? If that had not revealed anything I was going to disconnect the grounds too but it got dark before I could finish testing.

AllanJ
By the way, if there is no significant load on any circuits then neutral problems will not show up.
Well my previous testing had revealed a drop to around 90 volts with one or two light switched on that is why I was just using two lights.

PJmax
When you see a problem and need to go out and measure voltages at the outdoor panel, put the hair dryer in the metal pan, hopefully not turned all the way up, before leaving it unattended.
Yes that is what I did when I tested outside at the main panel yesterday with two lights on. At the inside panel I measured the voltage drop on one hot down to 90 volts and a rise on the other hot to 150 volts, at the outside panel the voltage was normal.

PJmax
If a breaker was trying to trip and it didn't, it would explode or the wire would burn.
All the neutrals from all the circuits should be connected to the neutral bar. Connecting them one at a time is not telling you or helping you in troubleshooting your problem.
Well I have tried everything else I could think of already, with all the neutrals connected. There is no corrosion in the panel it is clean. I took all the breakers off the panel the hot busses are clean. The lights go dim, the voltage measurement drops on one hot while rising on the other. Turning off all the other breakers except the circuit under test makes no difference. The voltages at the main panel outside are good while under the same load that causes the problem inside.
I disconnected the neutrals for a process of elimination to isolate the circuit being tested from all the others.
The breaker didn't explode or burn but the bulbs in the lamps blew.
I had to figure this out myself because no could tell me what to do. When I go back I will continue my tests, I will also disconnect all the grounds from the panel including the circuit under test, if the circuit goes dead with the grounds disconnected I will know it is an open neutral and it was trying to use the grounds instead. If the circuit under test works correctly while isolated from the others and with the grounds disconnected I will know the connection from the inside panel to the main supply is good and the problem is with one of the circuits in the house.
 

Last edited by ScareCrow2000; 04-27-15 at 10:49 AM.
  #31  
Old 04-27-15, 11:48 AM
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Why do you continue to ignore the most obvious source of the problem that I pointed out in post #26:
I discovered the three main 4 gauge cables are joined with black tape around the joints
(Not cables wires.) You need to shut off main power, remove the tape and see what was used to connect the wires together. They should not just be twisted together.
 
  #32  
Old 04-27-15, 05:42 PM
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"Yes that is what I did when I tested outside at the main panel yesterday with two lights on. At the inside panel I measured the voltage drop on one hot down to 90 volts and a rise on the other hot to 150 volts, at the outside panel the voltage was normal."

This would point you in the direction of checking for defects between the outside panel and the inside panel. Normally this part of the wiring would not be the responsibility of the power company.

It is a good idea not to get into the habit of unhooking a neutral without or before unhooking the corresponding hot. It is easy to forget reconnecting things and someone else might flip on the breaker, energizing the circuit and likely causing unpredictable things to happen. If the hot is energized while the neutral is unhooked, and if something is plugged in and switched on, then that neutral will be live.
 
  #33  
Old 04-27-15, 06:39 PM
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Check the main connections under the trailer. Then you can laugh at me when I'm wrong but at least you will have eliminated the obvious. Note there should be no connection out side of a junction box and no individual wires out side of conduit. That needs to be fixed.

Or as PJ wrote in post #25:
There should not be exposed joints under the motorhome. By exposed I mean not in a junction box.

There's a good chance the neutral splice there is bad. You don't have a hot wire issue.
 
  #34  
Old 04-27-15, 07:01 PM
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I disconnected the neutrals for a process of elimination to isolate the circuit being tested from all the others.
The breaker didn't explode or burn but the bulbs in the lamps blew.
This is exactly what happens when you open a neutral. You put 240 volts through the light bulbs.
 
  #35  
Old 04-27-15, 08:51 PM
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I went back out there today, narrowed it down to the bedroom/bathroom circuit so I decided to check the wiring at each receptacle and light. I started by disconnecting the RCD outlet in the bathroom and tying the wires together, and right there was the problem.
Without that RCD outlet connected Everything is now normal, voltages measured to neutral on both hots are equal (123.4v) and add up to the hot to hot voltage(247v), lights do not flicker when other lights are turned on and none of them go dim.
I connected the rest of the neutrals back up and turned lights on in every room, all is good.
I do not understand how an RCD outlet could have caused this problem which affected every room in the home. I hope this is not a symptom of something else.

ray2047
Why do you continue to ignore the most obvious source of the problem that I pointed out in post #26:
I'm not ignoring that, we had rainy weather last week and a severe storm at the weekend the ground is still very wet and I didn't want to crawl around in the mud I am going to check those connections when it dries up some.
 

Last edited by ScareCrow2000; 04-27-15 at 10:24 PM.
  #36  
Old 04-27-15, 09:53 PM
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If they are over or in mud that makes it even more likely that is your problem. If that is the problem your just spinning your wheels till it is fixed. Can you post some pictures of these wires and that connection? http://www.doityourself.com/forum/li...rt-images.html

Plumbers in my area where the crawl space under houses is often wet traditionally use 30# roofing felt under house when it is wet then just throw away when done. (You haven't had fun till you have laid in mud on a near freezing day to replace pipes that froze during the night.)
 
  #37  
Old 04-28-15, 09:20 AM
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If they are over or in mud that makes it even more likely that is your problem. If that is the problem your just spinning your wheels till it is fixed. Can you post some pictures of these wires and that connection?
Yes I will take some pictures of those connections, when I go back and check them out I will test them for continuity etc.
I really don't understand what is happening. After all, when a circuit in energized the current should only have two places it can go, to the neutral or to the ground, so how was a single RCD outlet messing up every circuit in the home ?
If the neutral is open the current had to be going to ground instead right ? I have not fixed an open neutral so if it was going to ground before it is going to ground now, but now everything appears to be working so what is happening now that wasn't happening before when the RCD outlet was connected ?
 
  #38  
Old 04-28-15, 02:11 PM
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I will test them for continuity
I wouldn't bother doing that. I'd just redo the connections being sure there is no corrosion. However from your brief description it sound like the whole thing will need to be replaced.

how was a single RCD outlet messing up every circuit in the home ?
Maybe the GFCI was coincidental to the real problem.
 

Last edited by ray2047; 04-28-15 at 05:08 PM.
  #39  
Old 04-28-15, 04:12 PM
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"I really don't understand what is happening. After all, when a circuit in energized the current should only have two places it can go, to the neutral or to the ground, so how was a single RCD outlet messing up every circuit in the home ?"

For typical homes there are three places that the power can come from or go (alternating current flows both ways). The places are the two hot terminals and the neutral (center) terminal on the pole transformer "secondary".

Generally there is one path from the first hot terminal to your panel (one hot service feed), one path from the other hot transformer terminal to your panel, and at least two paths (service neutral wire and earth) from the center terminal of the transformer to your panel.

The path through the earth (ground; soil; dirt) exists because there are ground rods on some utility poles that are connected to the service neutral and there is (should be) ground rods and maybe a water pipe connection to the neutral terminal bar (bus bar) in your panel. When the service neutral is in good and proper shape, its resistance is low enough that all current that should flow through it will do so with any current taking the (usually higher resistance) path through the dirt too small to cause erratic voltages.

Current will use any combination of these paths to its satisfaction. Figuring out exactly how much current goes each way and also the total amount of current that will flow can be complicated and is based on Ohm's Law.

Most likely you have an intermittent or loose connection in the neutral line between your inside panel and your meter. Most of the current is supposed to use that path but due to the poor or changeable connection, the current will use the other paths. When large amounts of current that are supposed to use the neutral feed line fail to do so, voltages about the entire system will become erratic.

If just the neutral in a combination 120/240 volt branch circuit (multiwire branch circuit) is compromised, just the voltages within that branch circuit will become erratic.

As the soil dries out, if there is indeed a bad connection soaking in the mud, the characteristics of that connection will be changing producing more unpredictable results.
 

Last edited by AllanJ; 04-28-15 at 04:39 PM.
  #40  
Old 04-28-15, 06:43 PM
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RCD outlet
Your profile says you are in Alabama (AL) however your terminology tells me you are from the EU or UK.
 
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