electrical - tester says hot/neu or hot/grd reversed

Page 1 of 2  
Off of 1 panel I have: 3 220V circuits 4 110V circuits
When one of the 220V breakers is on, all the 110 circuits display some kind of "error" -- either hot/neu reversed or hot/grn reversed, or in one case all 3 lights come on! (which is not suppose to be an option!). It's the same error on each circuit, just different errors depending on which circuit it is.
When I flip off that one 220V break, all the circuits read fine.
What could it be? The 220V circuit has 3 outlets on it. And they all work.
The 220V circuits use 3 wires - black, white, ground. Black and white go to the breaker.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
coloradotrout wrote:

(The white to the 220V breaker should have been remarked a different color like black or red. Also at the receptacles. Not encouraging.)
All 3 lights on can be caused by a floating ground - for instance if the ground was at 60V. Or if the ground was at 110V on the other hot wire.
H-N reverse could be caused with a floating ground if the ground was hot.
If the hot was not powered you could get H-G reversed if the ground was hot.
My guess is a floating ground. The ground voltage could be determined by leakage in the 220V circuits (or loads connected). These testers do not necessarily indicate reality.
Do loads on all circuits work (for instance lights are normally bright on the 110V circuits (or are H-N and H-H voltages normal).
If you have a known good receptacle elsewhere (particularly the ground) you could run an extension cord from it to your panel and measure voltages with respect to the good ground on the extension cord (including panel ground).
To test the ground, connect a light bulb from hot to ground (perhaps with only one 110V breaker on). If the bulb does not light the ground is open. The bulb should light from H-N.
--
bud--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The issues only exist when that 1 220V breaker is on. If I flip it off, all receptacles test out fine.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Cicuits ========================= a)110v - office lights and outlets b)110v - office AC - single outlet c)220v - office heat - hardwired
d)110v - shop lights e)110v - shop outlets f)220v - shop dust collector outlet - single 20A outlet g)220v - shop outlets - 3 20A outlets -- THIS IS THE ONE that when its breaker is on, seems to be what causes all the other circuits to be H- N, H-G, or in the case of the office AC, all the lights come on, which is a condition that the legend on the tester does not even address.
Lights, saws, drills, etc all seem to work fine.
I added d, f, and g. (d) used to be apart of (e), but I ran a seperate circuit.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Cicuits ========================a)110v - office lights and outlets b)110v - office AC - single outlet c)220v - office heat - hardwired
d)110v - shop lights e)110v - shop outlets f)220v - shop dust collector outlet - single 20A outlet g)220v - shop outlets - 3 20A outlets -- THIS IS THE ONE that when its breaker is on, seems to be what causes all the other circuits to be H- N, H-G, or in the case of the office AC, all the lights come on, which is a condition that the legend on the tester does not even address.
Lights, saws, drills, etc all seem to work fine.
I added d, f, and g. (d) used to be apart of (e), but I ran a seperate circuit.
*I would take apart that circuit (g) and see what's going on. Open up the 220 volt outlets. Open up the circuit breaker panel. Check all connections and make sure everything is wired correctly. After that check without anything plugged in. If there is still a problem check everything else starting with d and f.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
coloradotrout wrote:

If the building has unaffected outlets, I like Bud's idea of using an extension cord to bring in a good ground to check the ground and neutral at an affected outlet.
It could be more foolproof to check for ground and neutral voltage with reference to the bare cable at the service entrance. I'd use a volt meter. An extension cord can be used to carry outlet voltages to the cable, or a wire can be used to carry the cable ground to an outlet.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
DO NOT TAKE CHANCES WITH YOUR LIFE! If any of this is beyond your abilities/experience, don't do it! I'm simply assuming from your descrip that you have some kind of background to know enough to carry out simple troubleshooting procedures. ELECTRICITY KILLS, and pretty quickly. If it doesn't kill, it's also a good vegetable maker. If it doesn't turn you into a vegetable, it can still break a bone because of your knee-jerk reaction to the shock. In other words, you jump, your knee meets the wall, and breaks your kneecap! Or something gets you in the crotch and it's just a ball buster, but it's still pretty danred dangerous! Not to mention painful when you come to. Be considerate of those who may have to find your body so soon after Christmas and call a contractor if you can't do these things safely. It's too early in the year for a funeral or a series of hospital visits.
You just about have to have a miswire, IMO.
220Vac wiring & pictures: http://www.lowes.com/lowes/lkn?action=howTo&p=Improve/220outlet.html http://www.xomba.com/how_to_wire_a_220v_wall_outlet http://www.misterfixit.com/hotnot.htm http://forum.doityourself.com/home-automation/50063-220-volt-wiring.html

ARE THEY 220Vac OUtlets? Or 110V?
WHAT is plugged into them? 220V with 2 hots and an earth is known as 2-wire. Do you have any 3-wire (requireing 4 physical wires) plugged into them? Unplug everything for the testing.

You indicate a 220 ckt with 2 hots and an Earth. There ARE 220 ckts with 2 hots, neutral AND earth, but that's not what you described.
If turning on the 220Vac breaker is causing the 110V lines to display errors, then there is a fairly serious miswire somewhere. It obviously "feels" like the 220V ckt is miswired since turning it off gets you good indications on the 110V ckts.
You can do all this from the breaker box end if you have a friend to do the shorting/switching around at the other end.
You are apparently North America so 110 ckts have a hot, neutral and Earth connection (Blk, Wh, Grn( or bare)).
220 ckts should have 2 hots and one earth connection. Right? Assuming the black is properly 110V, then the white must be the other 110V leg, and should be tagged/marked/colored somehow as being Red. Between the two there will be 220V (blk to wh(red). .
The remaining third wire then is earth ground, and green if it's insulated. Right? There will be 110V between the Blk and Wh(Red) wires and the earth ground. The third wire should not be a Neutral; it should be ground. And it should earth the metal receptacle block. Even though they connect together in the breaker box, neutral and earth are NOT the same thing.
Except for the Earth connection, there should be NO voltages between the black of the 220 lines and the black of the 110 lines. It should measure 0Vac. From the red wire of the 220V line, there should be 220V between it and the black wire of the 110V lines. If it's just the opposite then there is a wiring reversal.
So if I were you I'd start by checking out the 220V ckts first, after verifying as much of the above as you can.
Turn OFF power at the Mains breaker so the whole panel is dead because I suspect you have a miswire in one of the hot leads. NOTE: THERE IS STILL POWER IN SOME AREAS OF THE BOX, SO TOUCH NOTHING YOU DON'T HAVE TO AND IF DOUBT, MEASURE FOR VOLTAGE FIRST!!
Using an ohmmeter (a Radio Shack $7 special works fine for this purpose) make sure nothing is plugged into ANY of the outlets, anything that's hard-wired in is turned OFF, and disconnect the wires from the breaker. Now check for no more than an ohm or so of resistance in ANY of the wires, and determine exactly where each wire goes. Check for an open circuit between each black and white wire of both ckts. If any show continuity, something is miswired. Check for continuity between the earth ground of the 220 to the earth of the 110, and an ohm or two higher between neutral of the 110 V ckt and the Gnd of the 220V ckt. In no event should you read more than a few ohms of resistance; it depends on how long the wires are exactly what number it will read. If you're lucky the numbers will be 0 ohms.
Hot needs to go to the Hot on its respective breaker, and nowhere else. Be sure to check that it goes NO WHERE ELSE! Because it might. Check by testing continuity to all the other wires it is NOT supposed to go to, too.
White, which apparently is really red, goes to the other breaker in the ganged breaker set and nowhere else. Be sure to check that it goes NO WHERE ELSE! Because it might. Check by testing continuity to all the other wires it is NOT supposed to go to, too.
There is no neutral involved. Make sure none of the wires is connected to neutral.
The Earth needs to go directly to the breaker box earthing blocks. And nowhere else.
If that seems confusing, there are step by steps that can be provided to make things clearer for using the ohmmeter. Haveing a reliable helper is a great asset too. All the measurements can be done from the breaker box end.
There are other methods too, but with power off is easily the safest when a miswire is suspected. If you need schematics, drawings, they can be provided too. Wikipedia is a good place to get general pics & information and has a bunch of links to more detailed information.
If none of this makes any sense to you, then you should bring in a qualified contractor to look at the job.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 24 Dec 2008 20:48:50 -0500, "Twayne"

Or get it on video. :)
Just kidding. Merry Christmas
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I will certainly have a look.
The 220V circuits are 3 wire - black, white (red) and bare (earth ground).
I was meticulous when I wired in the cicuits - d, f, and g. But it almost seems certain that the issue must be in the 3 outlet 220V circuit. When I turn off it's breaker, all the other 110v outlets test OK. The outlets are 20A outlets. They are wired one above the other, 3 in a row vertically. If I switched black and white (red) from one side of the outlet to the other would that cause any issues? Shouldn't right? It's still 110V on either side - should make no difference which side is black and which is white (red). At the breaker - black goes to one terminal of the breaker and white goes to the other - and ground goes to the ground block (not the neutral block).
I suppose one of those 20A 220v outlets could have a problem?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I will certainly have a look.
The 220V circuits are 3 wire - black, white (red) and bare (earth ground).
I was meticulous when I wired in the cicuits - d, f, and g. But it almost seems certain that the issue must be in the 3 outlet 220V circuit. When I turn off it's breaker, all the other 110v outlets test OK. The outlets are 20A outlets. They are wired one above the other, 3 in a row vertically. If I switched black and white (red) from one side of the outlet to the other would that cause any issues? Shouldn't right? It's still 110V on either side - should make no difference which side is black and which is white (red). At the breaker - black goes to one terminal of the breaker and white goes to the other - and ground goes to the ground block (not the neutral block).
I suppose one of those 20A 220v outlets could have a problem?
* My first thought is that there may be a problem with whatever is plugged into those outlets. You didn't mention if you had disconnected the equipment from the receptacles when you did your testing.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Problem Identified - Problem Solved
On that suspect 220v circuit there was one outlet that had a ground wire that was poking into the white (hot in the case of 220v).
Lesson -- clip off any wires that extend beyond the outlet. I had just wrapped the ground around the outlet post and tightened the screw down, but left 3/8" or so sticking out. That little amount, when pushed into the box, was able to penetrate into the white.
So , in essense, my ground circuit had 110v on it.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
coloradotrout wrote:

Nice to hear what the problem was.
But you can't have 110V on a ground unless you have a bad ground connection back the service. If the ground was continuous there would be high current which would trip the breaker or burn some wires open (probably at the point of your fault). That is the point of having a ground.
--
bud--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Understand. So, all the circuits check out OK now (the tester does not work on the 220v ones however). I was thinking the same -- if one side of the 220 was grounded, it would have tripped the 220v breaker, but it did not. So that suggests the ground may have an open somewhere - correct? Hmmm.. another mystery. Makes be wonder if the box has a good earth ground or not.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
coloradotrout wrote:

If the simple plug-in 3-lite testers indicate a problem, there probably is one.
They can not reliably indicate there is no problem. A high resistance ground is one of the problems they can not detect (they don't use enough current when testing).

Any receptacle that gave a "funny" indication had a bad ground. It could be a circuit or the whole panel.
Not only are some outlets not grounded, if a failure at one outlet makes that ground "hot" many other outlet grounds are "hot". Real bad condition.
To test the ground, connect a light bulb from hot to ground. If the bulb does not light the ground is open. The bulb should light at full brightness.

It is not an earth ground problem.
The "ground" wires return to the service. At that point there is a connection between the "grounds" and the incoming service neutral. (This is typically a screw from the neutral bus to the enclosure.) On a fault, like yours, the ground wires go back to the service panel, connect to the service neutral, and go to the power transformer. That gives a high current path that will trip a circuit breaker. This is a main function of "ground" wires, and will happen without an earth connection.
Connection of "ground" (and neutral) wires to the earth keeps a low potential with respect to the earth. If the "ground wire"-neutral bond at the service is missing, there will be some return through the earthing electrode, through the earth, to the earthing electrode at the transformer. If you had a quite good resistance to earth of 10 ohms, your fault (120V to earth) would produce a current of 12 amps - not likely to trip a 15A breaker - there would be a significant delay even if the breaker was fully loaded.
--
bud--




Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Bud,
So I should look in my panel and see that the neutral is grounded to the box?
I thought I recall seeing 3 large wires coming into the box - hot, hot, and neutral. The box itself then has a ground bar and two neutral bars ( I think). I do not recall seeing any neutral to box connection.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Suspect the OP does not understand wiring sufficiently and/or has made basic error in wiring.
Also is this being wired from the main panel of the house or pony panel? There is mention of "three wires coming into the panel"! And no connection between neutral and ground; so it's a sub panel?
Also we are talking 230 volt outlets; not what are sometimes called Edison outlets or here sometimes called 'split outlets'?????
Split outlets (allow you to plug in more load). Namely when the connection between the upper and lower parts of a duplex is deliberately broken by removing that link on the hot side of the duplex and a common neutral is used, the upper half uses one 115 volt leg (say red) and the other half uses the other leg (say black). Thus effectively two separate outlets on the same 230 volt common neutral circuit breaker.
And who is to say the pony (if indeed it is that) is wired correctly? Very confusing; but sounds like it would take less than an hour to sort out!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'm not wiring expert, but the panel was already in-place. From the pole there is a 100A breaker that feeds this panel.
I added the circuits noted - 2 x 220V and 1 x 110V. For the 110v, I wired white to the neutral bar (where the other 110v white wires were connected, the bare ground to the bare ground bar, and the black to the breaker. For the 220v circuits, bare ground to bare ground bar, white to one screw on the breaker, and black to the other screw. These are square D panel/breakers. Nothing fancy, all basic components.
Note my last post -- the detected problems are resolved, but the concern is I still have an open ground somewhere, else the previous problem would have trippped a breaker.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Sounds correct. We have all square D breakers in main panel and two pony panels and similar set up except we use red, black and white; wiring 230 volts outlets to red, black and of course ground. And 115 volt outlets to black and neutral white. The locations we have 230 volt outlets is above work benches. Agree it does now sound like an open ground somewhere and/or a ground miswired and acting as as a neutral in some previous wiring? BTW not trying to use one of those plug in tester to check 230 volt circuits???? As indicated by one poster each side (leg) of the 230 volts should have 115 volts to ground and to neutral. (and 230 volts between them). If not potential to ground as perhaps indicated, open ground somewhere.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
coloradotrout wrote: >>>>

If there is an open ground you really need to fix it. If receptacles on multiple circuits had "funny indications" I would suspect missing ground-neutral connection at the panel if it is a service panel. Else it might also be a defective ground on that circuit If it is a sub-panel maybe a defective ground in the feed. If it is a sub-panel in a different building, how is it fed - only 3 overhead wires? I gave you a ground test using a light bulb.
If it is a service panel - the utility supply will come in through a meter to the panel - there will be no disconnect between the utility connection and the main breaker in the panel.
If it is a service panel and wired to the National Electrical Code it will have - a heavy wire connected from neutral/ground bus to grounding electrode(s); in older installations the water service pipe; in newer installations an additional electrode, commonly a ground rod. - and a jumper between the neutral bus and the enclosure.
If it is not a service panel, but is fed from a different building there are options.
If there is a jumper between the neutral bus and enclosure, as I wrote in a different post, it is commonly a screw from the neutral bus to the enclosure. The SquareD panels I have seen it is an ordinary looking round or pan head screw about 10-32. Sometimes they are colored green. If it is not there, there should be an empty hole in the neutral bus. The bonding screw is not obvious at all.
If this is a separate building, like a garage, it probably needs to be wired similar to a service. (I have seen electricians argue about the relevant code sections.) You have not provided enough information
You may want to call an electrician.
For your 220V circuits, if you are using Romex or other cable, the "white" wire should have been covered with tape to make it a different color than white or green. It should have been re-colored wherever the wire appears. (If using fished wires, white shouldn't have been used.)
--
bud--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I have not tried the ground testing yet (light bulb). The tester now shows all circuits "correct". (but again, it's a 110 tester, so I cannot plug it into the 220v outlets)
All tools, lights, etc work.
But since the original problem was the ground on a 220v outlet had pierced the white wire (carrying 110v), the assertion here is that something must have been wrong with the ground else the breaker would have tripped. Seems reasonable. Seems like that outlet's ground wire must not be a good ground (or else electricity would have been continously flowing from 110v on one side of the 220v breaker to the ground. That just bugs me. In essence if there was a short, it should have tripped the 220v breaker -- or so I would think.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.