Grounding to neutral in an isolated system???

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!!! (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???:confused:

OK, TLDR (Too Long, Didn’t Read).
That said, I think you are going to have a hard time getting good answers remotely.

Off-grid systems are very different from grid-tied electrical wiring. You have both DC and AC circuits to worry about, along with lightning protection. I’m a EE, and I wouldn’t want to offer any advice without actually seeing your setup.

I would seriously consider talking to the guys at Home Power magazine - they are the experts. They may even have a discussion board.

I have no idea how they do it in your part of the world, but here in the U.S. the neutral and the safety ground are both connected together at one point and ONLY at one point. This point may or may not be inside the main breaker panel.

ETA: Just to clarify, in sub-panels, the neutral and the safety ground are NOT tied together. The neutral and ground only connect at one place, and that should be at or very close to the service entrance.

Older residential services made the connection to earth ground by attaching the ground/neutral from the main breaker box to the cold water pipe, as this was a good solid commonly available ground in most homes and buildings. When PVC pipe started to become common, the rules changed. Now a separate ground rod has to be used for the earth ground connection. However, you don’t want the water pipes to be floating as they could come in contact with a hot electrical line, so the cold water pipe still ends up having a connection to your ground/neutral connection. All of these connections tied together should be done close to each other, if possible.

That’s the grounding scheme used in the U.S. I know that it is used in other parts of the world (with some variation) but I can’t speak to your country’s rules and standards.

While isolated systems do exist, it is very rare for entire buildings to be isolated from ground (in an isolated system the neutral is left floating). This is because it is fairly difficult to maintain the isolation and you don’t get any warning if something shorts and you lose the isolation unless you specifically have instrumentation installed to detect it. Again, this is speaking from a U.S. perspective.

In my brief scan of your post I didn’t quite understand exactly how everything is connected and can’t comment on why the GFCI is tripping. Hopefully I will get more time later to read your post in more detail and I might be able to give you some advice then.

in the USA there are reasons that you might have more than one safety ground, like the locations being more than 50 feet apart. the neutral is connected to ground only at one point, usually where there is the electric meter or first disconnecting point.

you need to do what is both legal and safe in your country.

Home Power has information on all types of electrical systems and people from all parts of the globe, so that is a good suggestion. they are at

There’s already been comment from the US pov, so I will put my 2 cents in.

There are electrical systems used in AUS/NZ that are MEN (Multiple Earthed Neutral). At each main board the neutral is grounded. Sounds the same as for the US, right? But it’s not because we use three phase power where the phase to neutral voltage is 230vac and phase to phase is 415vac. The neutral in this system can be derived from the centre point of a star connected transformer. In this system, any RCD or GFCI devices can only be connected after the main board, as the ground-neutral connection is what they are designed to detect and trip on.

That may answer your second question. There may well be a connection on your upstairs sub-board that is between ground and neutral.

Look at this possibly confusing article about earthing systems.