Beach house - Earth Stake

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WanaGo

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#260170 14-Nov-2019 10:56

Hi All,

Another post on the same subject of our beach house.

House is 1940's era, has a ground/earth stake by the front door, approximately 2-3 meters from the main fuse box which is on an inside wall.

Soil type is sand. I am unsure how deep the stake goes, it looks original.

Main fuse box has the MEN link present.

What is the best way to determine if the earth stake is still OK, and hasn't rotted off etc. Is there a DIY way to do this, or do I need to call in a pro?

Thanks

WanaGo

mdooher

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#2353240 14-Nov-2019 14:03

No, you cant test it yourself because you need to remove the connection to the earth bar... if you have a bad neutral when you do that it can easily be good night nurse...that is why you need a sparky... as an aside your earth is probably rubbish, they all are but it doesn't matter as long as you have a good neutral connection. if the neutral drops off because it corrodes or gets taken out with a tree, well that is when you care about the earth.

Matthew

WanaGo

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#2353252 14-Nov-2019 14:23

Thanks Matthew.

So is it a relatively easy task for a Sparky to install a new earth stake?

How far do they typically go into the ground, do you know? Is it dependant on soil type?

Thanks for the information

WanaGo

timmmay

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#2353276 14-Nov-2019 15:08

I had a new earth installed a couple of years ago. I vaguely recall the electrician saying that testing it is difficult / expensive. Something to do with having to run a lot of power through it. Maybe someone can clarify. I could be completely wrong.

mdooher

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#2353282 14-Nov-2019 15:22

timmmay:

I had a new earth installed a couple of years ago. I vaguely recall the electrician saying that testing it is difficult / expensive. Something to do with having to run a lot of power through it. Maybe someone can clarify. I could be completely wrong.

Get a new electrician... it is easy and takes no time at all (plus inspection costs, and to be honest most just put it in and rely on the inspector to test it)

Matthew

mdooher

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#2353284 14-Nov-2019 15:28

WanaGo:

Thanks Matthew.

So is it a relatively easy task for a Sparky to install a new earth stake?

How far do they typically go into the ground, do you know? Is it dependant on soil type?

Thanks for the information

standard electrode, gets driven in 1.8m. Will require inspection my an inspector. (some sparkies might not get an inspection because there is a workaround in the regs but most good ones will.

Matthew

tripper1000

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#2353285 14-Nov-2019 15:31

WanaGo:

Thanks Matthew.

So is it a relatively easy task for a Sparky to install a new earth stake?

How far do they typically go into the ground, do you know? Is it dependant on soil type?

Thanks for the information

1.8 meters.

Regulations are here: (http://legislation.govt.nz/regulation/public/1997/0060/7.0/DLM229746.html)

Edit: Whoops, those have been revoked, but the replacement reg is listed (not sure why they publish revoked regulations).

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mugs2000

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#2353400 14-Nov-2019 16:11

Some years ago, we were installing a PABX at a business in Queenstown where the ground was alluvial. The trunk lines went back to a manual switchboard. Everything worked correctly locally, but we could not call the operator. I urinated on the earthing pipe, and the trunk line began to work. I suggested to the manager that he might have to periodically use a brine solution or something.

I hesitate to suggest that you do a similar thing here.

WanaGo

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#2353401 14-Nov-2019 16:14

Hahaha :)

Nice

WanaGo

mdooher

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#2353474 14-Nov-2019 16:55

mugs2000:

Some years ago, we were installing a PABX at a business in Queenstown where the ground was alluvial. The trunk lines went back to a manual switchboard. Everything worked correctly locally, but we could not call the operator. I urinated on the earthing pipe, and the trunk line began to work. I suggested to the manager that he might have to periodically use a brine solution or something.

I hesitate to suggest that you do a similar thing here.

Have peed on the earth stake many times to get it to pass inspection. fortunately these days inspectors don't worry too much as long as they get around 25ohms or so ...see my previous comments as to why. It is more the overall loop impedance that matters. To put it simply if you have a short circuit in your house you want enough current to flow to operate the pole fuse quickly (legally 4s... if possible 0.4s) i'm sure anyone can see why that would be a good idea

Matthew

WanaGo

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#2354224 15-Nov-2019 12:54

Here is a picture of the current earth stake

WanaGo

mdooher

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#2354234 15-Nov-2019 13:35

WanaGo:

Here is a picture of the current earth stake

I've seen worse, at least it wont be carrying the neighbors fault current :)

Matthew