# Electrical Question: Can you ground to neutral? **URL:** \ **Category:** Factual Questions\ **Created:** [May 16, 2005, 6:03am UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032 "2005-05-16T06:03:31Z")\ **Posts on this page:** 16\ **Page:** 3
**Author:** ![Uncommon\_Sense](https://avatars.discourse-cdn.com/v4/letter/u/f9ae1b/32.png) [@Uncommon\_Sense](https://boards.straightdope.com/u/Uncommon_Sense)\ **Post date:** [May 18, 2005, 12:47pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/41 "2005-05-18T12:47:30Z")
> [@Crafter\_Man](#): > > As far as grounding a GFCI receptacle, I see nothing wrong with it… if there’s a ground wire already run to the outlet box, then you will want to hook it up to the GFCI receptacle’s ground screw. That way, you’re protected in two ways. Right, if the ground is present and intact then use it. If the conditions of the OP exist where there is no ground in the system (old cloth covered cables, or knob and tube) then you have no ground to work with. ---
**Author:** ![Uncommon\_Sense](https://avatars.discourse-cdn.com/v4/letter/u/f9ae1b/32.png) [@Uncommon\_Sense](https://boards.straightdope.com/u/Uncommon_Sense)\ **Post date:** [May 18, 2005, 12:51pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/42 "2005-05-18T12:51:48Z")
Whoops, the OP doesn’t say there is no ground, it came up later in the thread as a ‘what if’. ---
**Author:** ![Desmostylus](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@Desmostylus](https://boards.straightdope.com/u/Desmostylus)\ **Post date:** [May 18, 2005, 12:52pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/43 "2005-05-18T12:52:03Z")
> [@Uncommon Sense](#): > > David’s response in the second post was directly referring to the conditions in the OP and he is correct. By using the neutral as the ground on a GFCI you are essentially making the ‘neutral to ground bond’ outside of the main service. You are also now combining the neutral and the ground in the system and in the electroncs of the GFCI, thereby defeating the design of the GFCI. > This has to do with the way the GFCI itself works and **Crafter** and/or **David** would know more about that. Just to clarify a bit how a GFCI works. It measures the difference between the current flowing out through the active wire, and the current flowing back in through the neutral wire. Ideally, the difference is zero. If it isn’t zero, it’s because some current is flowing back through something other than the neutral wire, e.g. through your body to ground, because you’ve got one hand on a faulty toaster and the other hand on the kitchen sink. If you earth the neutral at some point beyond the GFCI, part of the current that _should_ flow back through the neutral _will_ flow back through the ground wire. The current flowing back through the ground wire will trip the GFCI. So it’s not really dangerous, it’ll just render the circuit useless. ---
**Author:** ![Desmostylus](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@Desmostylus](https://boards.straightdope.com/u/Desmostylus)\ **Post date:** [May 18, 2005, 1:00pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/44 "2005-05-18T13:00:53Z")
> [@Desmostylus](#): > > …it’ll just render the circuit useless. By this I mean the electrical outlets, not the GFCI. As soon as you plug pretty much anything into on of the outlets on the circuit, the GFCI will trip. ---
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [May 18, 2005, 2:13pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/45 "2005-05-18T14:13:43Z")
> [@Desmostylus](#): > > By this I mean the electrical outlets, not the GFCI. As soon as you plug pretty much anything into on of the outlets on the circuit, the GFCI will trip. Yes. If the green is connected to the white beyond the GFI it furnishes a path outside the GFI for some of the return current. This unbalances the current in the black and white leads through the GFI by enough that it will always trip. ---
**Author:** ![Waterman](https://avatars.discourse-cdn.com/v4/letter/w/b2d939/32.png) [@Waterman](https://boards.straightdope.com/u/Waterman)\ **Post date:** [May 20, 2005, 4:20am UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/46 "2005-05-20T04:20:49Z")
Is “knob and tube” where you have bare wire and insulators as in the attics of older (as I’ve seen in pre 1920’s) homes? ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [May 20, 2005, 5:20am UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/47 "2005-05-20T05:20:15Z")
> [@Waterman](#): > > Is “knob and tube” where you have bare wire and insulators as in the attics of older (as I’ve seen in pre 1920’s) homes? Yep. Knob and tube wiring gives me the willies every time I see it. Personally, I think if your house has it then you should have it all replaced. Technically though, as long as it is well maintained you don’t need to replace it. ---
**Author:** ![PosterChild](https://avatars.discourse-cdn.com/v4/letter/p/e274bd/32.png) [@PosterChild](https://boards.straightdope.com/u/PosterChild)\ **Post date:** [May 20, 2005, 6:22am UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/48 "2005-05-20T06:22:52Z")
> [@](#): > > If you earth the neutral at some point beyond the GFCI, part of the current that _should_ flow back through the neutral _will_ flow back through the ground wire. The current flowing back through the ground wire will trip the GFCI. Does “beyond” the GFCI mean on a circuit farther from the fuse box than the GFCI? Does it include the ground terminal on the GFCI outlet- if you ran a wire from the ground terminal on the GFCI outlet to the neural wire in the wall near the outlet (in the electrical box that contains the GFCI outlet), would that have current flowing through it? PC ---
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [May 20, 2005, 6:24am UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/49 "2005-05-20T06:24:00Z")
> [@engineer\_comp\_geek](#): > > Yep. > > Knob and tube wiring gives me the willies every time I see it. Personally, I think if your house has it then you should have it all replaced. Technically though, as long as it is well maintained you don’t need to replace it. I worked with my uncle wiring farm houses for REA (Rural Electrification Administration) in 1940. Lots of them had the old porcelain standoff insulators and bare wires for their wind charger set-ups. The wind charger was a wind driven, 24 V. truck generator that was used to charge lead-acid batteries to provide electric lighting for farms before REA was available. Several of the farm owners tried to get us to use the existing wind charger wiring for the REA power. Of course that was strickly forbidden by REA and in any case, even if it hadn’t been my uncle was a pretty conscientious guy and wouldn’t have done it anyway. ---
**Author:** ![Desmostylus](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@Desmostylus](https://boards.straightdope.com/u/Desmostylus)\ **Post date:** [May 20, 2005, 8:59am UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/50 "2005-05-20T08:59:26Z")
> [@PosterChild](#): > > Does “beyond” the GFCI mean on a circuit farther from the fuse box than the GFCI? Yes. > [@PosterChild](#): > > Does it include the ground terminal on the GFCI outlet- if you ran a wire from the ground terminal on the GFCI outlet to the neural wire in the wall near the outlet (in the electrical box that contains the GFCI outlet), would that have current flowing through it? > PC Yes. ---
**Author:** ![junglegrrl](https://avatars.discourse-cdn.com/v4/letter/j/8491ac/32.png) [@junglegrrl](https://boards.straightdope.com/u/junglegrrl)\ **Post date:** [January 6, 2014, 6:42pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/51 "2014-01-06T18:42:59Z")
> [@Uncommon\_Sense](#): > > True, the code forbids you to make a ground to nuetral bond outside of the main panel. > > In the even that you would like to install a _grounded_ outlet where there was none previously due to the lack of grounding conductor in the circuit one **may** install a GFCI device. > When a GFCI receptacle is installed on a non-grounded system, the GFCI must not be connected to an equipment ground. Also, the receptacle must be labeled “No equipment ground”. > You can now use the outlet as you would a normal grounded receptacle as you are protected from line to nuetral leakage and since no equipment ground exists you need not be concerned about leakage to ground in the typical sense. Okay so my question is related to all of this thread but slightly different since I live in a third world country and have done all of my own wiring based on my extremely limited knowledge of such (self-taught), and the advice of other ‘electricians’ (mostly self taught) First I will ask the questions, then i will give a detailed explanation of my systems to help you answer it, I know it is all pretty ridiculous by US/Canadian standards, but hey, we are in the thrid world and I am doing this all myself because the ‘electricans’ here are lazy, unreliable, and equally if not more so ignorant than me!!! :smack: (Yes REALLY!) So after you finish laughing, PLEASE HELP ME! 1. Should I have a jumper wire that joins the ground bar and the neutral bar inside the subpanel? (there is not one joining them now, they are isolated from one another) This question applies to all systems since all the boxes are this way ANd further, IF I NEED TO PUT IN A JUMPER WIRE, do i need to do so only at the FIRST main panel where the power initially comes in and goes to subpanels or at each box? (there are three boxes in my microhydro system,one at the turbine house, one at the first house it runs to, and one at our house) 2. Why does throwing the 2 pole switch that SHOULD allow me to switch the load into my upstairs subpanel between (to the left) my hydro and (to the right) my solar array system trip the GFCI outlet right BEFORE the switch (from the hydro system) but NOT when it is only running the other circuits (ie not going into the upstairs subpanel and its circuits)? Does this mean there is a ground fault in my upstairs circuits? How do i figure out where the fault is? I have three separate renewable energy systems, two solar arrays and one micro-hydro electric turbine. Each system has its own separate charge controller and inverter. I also have boht solar arrays grounded to a single rod via the subpanel box that runs theri circuits into our upstairs. The micro hydro is located about 1500 feet from our house down the hill and is grounded with a grounding rod from the ground bar inside a sub panel box at the turbine house, again in a small house about 300 feet away where it enters the main breaker box and a third time here at our house where it enters the house at that houses main panel. The solar arrays both run into a subpanel box upstairs and the ground bar is connected to a ground rod on the opposite side of the house from the ground rod for the microhydro system. Originally I had a selftaught electrician friend install the breaker box (a small ge subpanel box) in the microhydro turbine house and he had the neutral and the ground bars tied together via a jumper wire. However he wired the divert load controller incorrectly (put a jumper pin over the wrong pins) which ended up frying our batteries. After i figured out (by reading the manual and doing it myself) what he had done wrong and put the jumper pin into the correct position, we replaced the batteries and since then it has all worked correctly. However it seemed to be using up excess energy and when I asked another friend who is a psuedo electrician about it he looked at the systems and said I should NEVEr cross the neutral to the ground that it just leaks current that way and wastes energy. So I, on his advice, isolated the neutral bar from the ground bar. I did not notice a big difference, but it remains that way now. So on that same principle when I installed the solar arrays I also did not connect the ground to the neutral. (they are not joined via a jumper wire but are each on their own bars. the ground bar is connected to the rod, and both solar array systems ground at that bar, as I said.) I also installed a circuit that runs from the main panel downstairs (micro hydro system) to a two pole knife blade switch. My goal was to allow this switch to make it simple to shift the incoming power for our circuits upstairs between the solar array system (there was only one at that time) and the microhydro so that ion rainy days when the battery bank was low for our solar array we could shift to hydro power and on sunny days, esp. in the dry season when the water flow goes down, we could allow the upstairs and the single circuit from that box that extends downstairs to an outlet behind our chest freezer/fridge to run only on solar and this way during dry season when there is more than enough solar output to supply these large draw appliances we can just unplug them from the hydro and plug them into the solar. As for finding a fault in the ground upstairs I tried plugging in one of those circuit testers which you just plug into an outlet at all the outlets and they all lit up with the ‘correct’ sequence which leads me to believe a ground fault is not the problem. NOW, since all of this, after installed the second solar array system (with its own inverter and battery bank etc) and since I could not figure out why the switch would not work, I hooked up a battery maintainer/chargers to each of the solar systems which should have allowed the hydro system to which they were plugged in, to keep the battery banks always full. However at that time I was forced to spend and entire month away from home and my husband was here but knows less than nothing about electric and during that month it all (the solar arrays) went to s\*\*T which is to say when I returned the one battery maintainer read check/replace battery, the other one shut off due to an auto off feature (i think) and the battery banks are reading less than 10 volts!!! (they should be 12!!!) I disconnected the maintainers and shut of all the circuits just to allow the banks to refill, but they do not hold any charge. I have concluded that the battery maintainers ruined, via overcharging?, the batteries somehow… but this does not quite make sense since they are both the more expensive microprocesser controlled variety (schumacher brand) which I got specifically so that they WOULD NOT overcharge my batteries!!! Now the one inverter went out completely that is to say it will not even turn on, most likely a blown fuse. The other appears to work fine but shows a reading of about 9-10 volts at night and about 13 during the day when the panels are giving it juice. However, even when it reads at 13, if I turn on the breakers it gives intermittent power it blinks on and off… totally unusable!!! The other possible factor here is that the roof developed a leak while I was gone and it appears (based on the watermarks) that the inverters or other components (charge controllers/battery chargers) may have gotten a bit wet. They were not wet when I came home but may have dried off since? So that is my whole story… BIG PROBLEMS!!! as I said… can anyone help me???:smack::smack::smack:😕:(:eek: ---
**Author:** ![junglegrrl](https://avatars.discourse-cdn.com/v4/letter/j/8491ac/32.png) [@junglegrrl](https://boards.straightdope.com/u/junglegrrl)\ **Post date:** [January 6, 2014, 6:47pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/52 "2014-01-06T18:47:04Z")
Okay so my question is related to all of this thread but slightly different since I live in a third world country and have done all of my own wiring based on my extremely limited knowledge of such (self-taught), and the advice of other ‘electricians’ (mostly self taught) First I will ask the questions, then i will give a detailed explanation of my systems to help you answer it, I know it is all pretty ridiculous by US/Canadian standards, but hey, we are in the thrid world and I am doing this all myself because the ‘electricans’ here are lazy, unreliable, and equally if not more so ignorant than me!!! :smack: (Yes REALLY!) So after you finish laughing, PLEASE HELP ME! 1. Should I have a jumper wire that joins the ground bar and the neutral bar inside the subpanel? (there is not one joining them now, they are isolated from one another) This question applies to all systems since all the boxes are this way ANd further, IF I NEED TO PUT IN A JUMPER WIRE, do i need to do so only at the FIRST main panel where the power initially comes in and goes to subpanels or at each box? (there are three boxes in my microhydro system,one at the turbine house, one at the first house it runs to, and one at our house) 2. Why does throwing the 2 pole switch that SHOULD allow me to switch the load into my upstairs subpanel between (to the left) my hydro and (to the right) my solar array system trip the GFCI outlet right BEFORE the switch (from the hydro system) but NOT when it is only running the other circuits (ie not going into the upstairs subpanel and its circuits)? Does this mean there is a ground fault in my upstairs circuits? How do i figure out where the fault is? I have three separate renewable energy systems, two solar arrays and one micro-hydro electric turbine. Each system has its own separate charge controller and inverter. I also have boht solar arrays grounded to a single rod via the subpanel box that runs theri circuits into our upstairs. The micro hydro is located about 1500 feet from our house down the hill and is grounded with a grounding rod from the ground bar inside a sub panel box at the turbine house, again in a small house about 300 feet away where it enters the main breaker box and a third time here at our house where it enters the house at that houses main panel. The solar arrays both run into a subpanel box upstairs and the ground bar is connected to a ground rod on the opposite side of the house from the ground rod for the microhydro system. Originally I had a selftaught electrician friend install the breaker box (a small ge subpanel box) in the microhydro turbine house and he had the neutral and the ground bars tied together via a jumper wire. However he wired the divert load controller incorrectly (put a jumper pin over the wrong pins) which ended up frying our batteries. After i figured out (by reading the manual and doing it myself) what he had done wrong and put the jumper pin into the correct position, we replaced the batteries and since then it has all worked correctly. However it seemed to be using up excess energy and when I asked another friend who is a psuedo electrician about it he looked at the systems and said I should NEVEr cross the neutral to the ground that it just leaks current that way and wastes energy. So I, on his advice, isolated the neutral bar from the ground bar. I did not notice a big difference, but it remains that way now. So on that same principle when I installed the solar arrays I also did not connect the ground to the neutral. (they are not joined via a jumper wire but are each on their own bars. the ground bar is connected to the rod, and both solar array systems ground at that bar, as I said.) I also installed a circuit that runs from the main panel downstairs (micro hydro system) to a two pole knife blade switch. My goal was to allow this switch to make it simple to shift the incoming power for our circuits upstairs between the solar array system (there was only one at that time) and the microhydro so that ion rainy days when the battery bank was low for our solar array we could shift to hydro power and on sunny days, esp. in the dry season when the water flow goes down, we could allow the upstairs and the single circuit from that box that extends downstairs to an outlet behind our chest freezer/fridge to run only on solar and this way during dry season when there is more than enough solar output to supply these large draw appliances we can just unplug them from the hydro and plug them into the solar. As for finding a fault in the ground upstairs I tried plugging in one of those circuit testers which you just plug into an outlet at all the outlets and they all lit up with the ‘correct’ sequence which leads me to believe a ground fault is not the problem. NOW, since all of this, after installed the second solar array system (with its own inverter and battery bank etc) and since I could not figure out why the switch would not work, I hooked up a battery maintainer/chargers to each of the solar systems which should have allowed the hydro system to which they were plugged in, to keep the battery banks always full. However at that time I was forced to spend and entire month away from home and my husband was here but knows less than nothing about electric and during that month it all (the solar arrays) went to s\*\*T which is to say when I returned the one battery maintainer read check/replace battery, the other one shut off due to an auto off feature (i think) and the battery banks are reading less than 10 volts!!! (they should be 12!!!) I disconnected the maintainers and shut of all the circuits just to allow the banks to refill, but they do not hold any charge. I have concluded that the battery maintainers ruined, via overcharging?, the batteries somehow… but this does not quite make sense since they are both the more expensive microprocesser controlled variety (schumacher brand) which I got specifically so that they WOULD NOT overcharge my batteries!!! Now the one inverter went out completely that is to say it will not even turn on, most likely a blown fuse. The other appears to work fine but shows a reading of about 9-10 volts at night and about 13 during the day when the panels are giving it juice. However, even when it reads at 13, if I turn on the breakers it gives intermittent power it blinks on and off… totally unusable!!! The other possible factor here is that the roof developed a leak while I was gone and it appears (based on the watermarks) that the inverters or other components (charge controllers/battery chargers) may have gotten a bit wet. They were not wet when I came home but may have dried off since? So that is my whole story… BIG PROBLEMS!!! as I said… can anyone help me??? ---
**Author:** ![junglegrrl](https://avatars.discourse-cdn.com/v4/letter/j/8491ac/32.png) [@junglegrrl](https://boards.straightdope.com/u/junglegrrl)\ **Post date:** [January 6, 2014, 7:13pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/53 "2014-01-06T19:13:43Z")
> [@engineer\_comp\_geek](#): > > The transformer outside of your house is going to have the effect of isolating you from the power system’s ground system. You need to ground your side of the transformer. > > The power plant also grounds its side of things, and different segments of the transmission system (power lines, transformers, etc) will also be grounded. > > Technically, an ungrounded (or isolated) system is safer. In an isolated system, you can touch either wire and earth ground and not get shocked. The problem with running large complex isolated systems it that mother nature tends to occasionally find some way of grounding part of your system for you, so what you end up with is a randomly grounded system instead of an isolated system. A predictably grounded system is better than a randomly grounded one, so that’s what we use. There are places where isolated power is used though. Hospitals use isolated power. If you are unfortunate enough to be in a hospital, look for the red outlets. They are isolated. Hospitals go through great pains to keep their isolated power systems isolated, and its difficult enough for them to keep it isolated and they only have one building to deal with, not thousands of buildings like the power company does. > > FYI there’s a handbook of isolated power, similar to the handbook for the national electric code. The introduction of the book spends several pages on the history of isolated power, and on electrical safety and grounding in general, and hits on many of the topics discussed in this thread. So in an isolated system do you still want to put a jumper wire into the box to join neutral to earth? does this waste much electricity? Is it a lot safer? (see my other posts for details) ---
**Author:** ![junglegrrl](https://avatars.discourse-cdn.com/v4/letter/j/8491ac/32.png) [@junglegrrl](https://boards.straightdope.com/u/junglegrrl)\ **Post date:** [January 6, 2014, 7:18pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/54 "2014-01-06T19:18:01Z")
is this what i have going on? an open neutral since they are not bonded at the box? ---
**Author:** ![junglegrrl](https://avatars.discourse-cdn.com/v4/letter/j/8491ac/32.png) [@junglegrrl](https://boards.straightdope.com/u/junglegrrl)\ **Post date:** [January 6, 2014, 7:23pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/55 "2014-01-06T19:23:05Z")
> [@Desmostylus](#): > > Just to clarify a bit how a GFCI works. It measures the difference between the current flowing out through the active wire, and the current flowing back in through the neutral wire. Ideally, the difference is zero. If it isn’t zero, it’s because some current is flowing back through something other than the neutral wire, e.g. through your body to ground, because you’ve got one hand on a faulty toaster and the other hand on the kitchen sink. > > If you earth the neutral at some point beyond the GFCI, part of the current that _should_ flow back through the neutral _will_ flow back through the ground wire. The current flowing back through the ground wire will trip the GFCI. So it’s not really dangerous, it’ll just render the circuit useless. Maybe this is what is happening that trips the GFCI when I try to throw the switch since then the system is effectively grounded both at the sub-panel for the upstair (which normally grounds the separate sola r array system) and the downstairs box (from the micro hydro???) If this is the case what can i do??? ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [January 6, 2014, 9:49pm UTC](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032/56 "2014-01-06T21:49:51Z")
**Moderator Action** Welcome to the SDMB, **junglegrrl**. Please note that we do not allow cross-posting or multiple posting here, as you have done with this question. Since your question is better suited to another thread anyway I will keep the new thread you created open and will close this one instead. The new thread is here: > **[Grounding to neutral in an isolated system???](https://boards.straightdope.com/sdmb/showthread.php?t=712285)** > > Okay so my question is related to all of this thread but slightly different since I live in a third world country and have done all of my own wiring based on my extremely limited knowledge of such (self-taught), and the advice of other ‘electricians’... Thread closed. [Previous page](https://boards.straightdope.com/t/electrical-question-can-you-ground-to-neutral/304032.md?page=2)