Earth Spike

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warrenpfo

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Good morning. I have looked high and low around the house but can't seem to find an earth spike for our house.

I can see the geyser, copper pipes and incoming supply all have an earth but I want to install a central earth spike for the house and so wanted to ask what the criteria are for selecting a suitable location might be?
 
warrenpfo said:
Good morning. I have looked high and low around the house but can't seem to find an earth spike for our house.

I can see the geyser, copper pipes and incoming supply all have an earth but I want to install a central earth spike for the house and so wanted to ask what the criteria are for selecting a suitable location might be?
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I had a new one installed after we moved in (despite certificate), guys installed it as close to the DB board as possible so that the cable run wasn’t too long
 
Thanks guys.

Doing a bit of googling it seems elsewhere in the world you need an 8ft rod of ideally solid copper where here in SA they range from about 800mm to 1.5m and can be either copper or copper bonded.

As close to DB makes sense, I will have not only my DB but also solar panels/rails connected to it aswell.
 
Username: said:
Two things at play here that many people don't understand.

You get earthing and bonding

To prevent electric shock and earth leakage protection to function all metallic parts must be bonded to a common earth point.

This earth point is tied down to earth typically at the mini substations star point at the transformer as we use TNS or TNCS in South Africa. For this no local earth spike is required.


When you install solar panels on your roof or have a high mast in your yard or thatch roof you need earth spikes as path for lighting to travel down safely into the earth.

Many time the copper gets stolen at the minisubstations leaving a floating neutral / earth then electricians installs a local earth spike to address the short coming.
.
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When I sold my previous township house, the electrician installed a rod. So it was for copper theft, interesting.
 
you shouldnt need to add anything to your muni earth unless you have problems related to earth/neutral for external ancillaries panel frames ,inverter casing , electric fences etc they get bonded to be the same potential .its not allways a good idea to bond your house to the spike as well .
 
warrenpfo said:
Good morning. I have looked high and low around the house but can't seem to find an earth spike for our house.

I can see the geyser, copper pipes and incoming supply all have an earth but I want to install a central earth spike for the house and so wanted to ask what the criteria are for selecting a suitable location might be?
Click to expand...

Did you follow the earth cable from the DB board?
 
warrenpfo said:
Good morning. I have looked high and low around the house but can't seem to find an earth spike for our house.

I can see the geyser, copper pipes and incoming supply all have an earth but I want to install a central earth spike for the house and so wanted to ask what the criteria are for selecting a suitable location might be?
Click to expand...
What exactly is it that you want to achieve with an earth spike? "for the house" is not a good enough reason. What are you trying to achieve?
 
We just used a 3 metre rebar rod here at work with a 5 pound hammer
Cheap and does the trick
 
RonSwanson said:
What exactly is it that you want to achieve with an earth spike? "for the house" is not a good enough reason. What are you trying to achieve?
Click to expand...
Sorry not sure how to do one reply but with multiple quotes.

I was always advised and maybe incorrectly that you should not rely on the municipal earth as apparently there are stories of work being done and the earth not being connected back and so a ground spike is always a good thing to have.

We have been in our place 5 years without issue and I am about to install solar and so am doing some preliminary checks to ground my instalation and noticed there was no earth rod.
 
warrenpfo said:
Sorry not sure how to do one reply but with multiple quotes.

I wax always advised and maybe incorrectly that you should not rely on the municipal earth as apparently thete are stories of work being done and the earth not being connected back and do a ground spike is always a good thing to have.

We have been in our place 5 years without issue and I am about to install solar and do am doing dome preliminary checks to ground my instalation and noticed there was no earth rod.
Click to expand...
you only need to bond the external frames and casings etc to an earth spike .dont connect that to any earth in your house .your muni earth is sufficient and to fiddle is not gooood .and for a lightning strike it wont do diddley squat any way ,its only really to dissipate static safely so your hair doesnt stand up when you walk past the panells.
 
I certainly dont want to fiddle but rather just make sure that the advise of not trusting municipal grounding is an old wife's tale I guess.

Happy to just bond my solar rails/panels to a rod and the rest to the home db
 
warrenpfo said:
I certainly dont want to fiddle but rather just make sure that the advise of not trusting municipal grounding is an old wife's tale I guess.

Happy to just bond my solar rails/panels to a rod and the rest to the home db
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you can do lots with good bonding that may help in the event of a strike .put the rod where you can easily pee on it every night to keep the soil moist
 
warrenpfo said:
Sorry not sure how to do one reply but with multiple quotes.

I was always advised and maybe incorrectly that you should not rely on the municipal earth as apparently there are stories of work being done and the earth not being connected back and so a ground spike is always a good thing to have.

We have been in our place 5 years without issue and I am about to install solar and so am doing some preliminary checks to ground my instalation and noticed there was no earth rod.
Click to expand...
you should be able to use aluminium earth cable for the run down to the spike ,it sometimes is easier to get the potential down and is cheaper than 10mm copper .
 
warrenpfo said:
Sorry not sure how to do one reply but with multiple quotes.

I was always advised and maybe incorrectly that you should not rely on the municipal earth as apparently there are stories of work being done and the earth not being connected back and so a ground spike is always a good thing to have.

We have been in our place 5 years without issue and I am about to install solar and so am doing some preliminary checks to ground my instalation and noticed there was no earth rod.
Click to expand...
There's an easy way to check your municipal earth <--> neutral bond: test your earth leakage. If it works, then it is good to go. No sense in creating multiple earths for no good reason, in fact this can actually cause issues.

If you install a hybrid or grid-tied inverter, then the inverter may disconnect from the grid and operate in islanding mode. Because you get your earth<-->neutral bond from the municipality, you may be left without one, rendering your RCD / earth leakage unit inoperable. Previously it did not matter, because you did not have any electricity to shock yourself to death with in the event of a fault, but now you have an inverter making AC current from batteries, wind and/ or solar power. So you may need a earth neutral bridge relay, which senses the grid is down ( and thus the earth neutral bond) and it temporarily activates a bond from the neutral to a secondary earth (which is typically 3x 1.2m earth rods driven into the ground about 1m apart), so that your RCD / earth leakage can work during the grid outage. When the grid comes back, the relay clicks out and the original municipal earth neutral bond returns. Note that at no time is there two simultaneous earth neutral bonds, always one only.

When you install solar panels, you will need to ground them for transient currents / induced voltages, and then you can use the 3x 1.2m earth rods for that, as long as it is as close as possible to the panels. It also mitigates overcurrent situations in the event of a fault on the DC wiring.
 
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