How do you install your earth stakes?

[Superspark23]

Just been working on site in an open park. No building around and the likly hood of hitting an cable seemed remote or anything for that matter. We could see exactly where the Incoming cable would run and we had a good idea where the pipe work was. but anyway, the guy i was working with insisted that we dug the full legnth of 2 rods, just to make absolutely certain we wouldn't hit a thing. A bit OTT don't you think?

I've whacked loads of stakes in, in built up area's never hit a thing to my knowledge, to me we wasted a good day and half for nothing when the job would have probably taken 1/2 day to complete if we just whacked the stake in.

 

[Engineer54]

Took you a day to dig 1.2metre?? I take it that's all you installed a 1.2m rod, as that's what seems to be the norm these days??

Not a good idea at the best of times, that ground is going to take at least a year to fully compact around the rod, even if you did do a bit of manual compaction of what you dug out.... So any readings you took need retaking at a much later date, preferably when the ground is frozen ...that'll give you a much better understanding of the level of earthing you have provided to your installation!!!

 

[Guest123]

If there is any doubt, CAT the ground first.

I've never dug out the ground where the rods go beforehand to check, IMO the readings would be affected by the now loose soil around them. Did you add any soil conditioner when you backfilled???

 

[Knobhead]

As Engineer 54 said you’ve ruined the ground by digging the trench.

As for just whacking a spike in anywhere can you let us know where your based I want to give it a wide berth. I’ve seen the aftermath of a spike going through a live 11KV cable, not pretty! For gods sake try and take care of yourself, the way you are going you won’t be around long.

The 11KV cable I fired an explosive spike in to it, got the wrong cable!

 

[nickblake]

As Engineer 54 said you’ve ruined the ground by digging the trench.

As for just whacking a spike in anywhere can you let us know where your based I want to give it a wide berth. I’ve seen the aftermath of a spike going through a live 11KV cable, not pretty! For gods sake try and take care of yourself, the way you are going you won’t be around long.

The 11KV cable I fired an explosive spike in to it, got the wrong cable!

least he'd have doug the hole ,sorry that was mean just couldnt resist , as Lenny has said cat the ground

 

[Knobhead]

"Did you add any soil conditioner when you backfilled???"

Frank Inness No.5. Tomatoes are coming up a treat!


Lenny what do you use for ground conditioning? The best I’ve ever come across was when I last did a substation earth nest, cow sh*t and p*ss, we buried the mat under 10 tons of it. The foreman was in his 60’s, he knew what he was doing! We had to resort to explosives to get a good depth, but where we worked that wasn’t a problem. The grass was nice and green afterwards.

 

[Guest123]

Bentonite....

AN Wallis Earthing and Lightning Protection :: A.N. Wallis

 

[Marvo]

If I'm remotely suspecting services underneath I'll dig to 1.5 - 2 meters then whack the 20mm spikes in. The records of buried services around here are a joke and we don't have the technology around to scan blow ground. We do use a minimum of 5 x 2.3 meter spikes on top of each other though so 90% of the rod is still going through hard-pan. The last one we knocked in we needed 8 rods depth to get a reading of < 20 ohm

A 1.2 meter spike in disturbed ground will be pretty much worthless.

 

[nickblake]

Bentonite....

AN Wallis Earthing and Lightning Protection :: A.N. Wallis

wish i new about that when i did a rod for a caravan on a beach , ended up installing it in a stream , worked a treat mind o.89 ohms enloced the connections and covered them with grease ,been tested 3 or 4 times since and the readings are stable

 

[mayfair]

1m 10 mm sds drill in first, fill the hole with water then a big hammer

 

[telectrix]

i'll make sure my hammer is fully insulated, just in case i hit a cable. don't know how good the insulation needs to be for 11kV, at least a roll of gaffer tape round the handle and a pair of steptoe gloves.

 

[mayfair]

Plus wellies of course.

i'll make sure my hammer is fully insulated, just in case i hit a cable. don't know how good the insulation needs to be for 11kV, at least a roll of gaffer tape round the handle and a pair of steptoe gloves.

 

[Engineer54]

Bentonite....

Lenny, Bentonite, isn't a a ground conditioner it serves as an electrode (earth rod) expander/enhancer. To use bentonite or similar, you would have to drill a hole(s), say 50 to 75mm dia, fill the hole with the bentonite slurry then drop the electrode(s) in, Maybe driving in say 30cm, if you want the electrode solid. Results from using this method over driven rods in bad ground conditions, can be exceptional


There are many ground conditioners, the likes of which magnesium sulphate, rough rock salt are just two, but are generally the most common. Normally you would hollow out a ring, or a depression surrounding the top of the electrode and fill with the conditioner, watering it in. There are two main problems with this method, if you can call them that. ...1/. They can be mildly to quite corrosive to the electrode rod, depending on the material used. 2 /. Requires ongoing or regular top-ups as they will eventually wash thru the surrounding soil beyond the rod depth.
There are modern ground conditioners, many based on Magnesium sulphate that are far less corrosive and are longer lasting, but can cost 1.5 times the cost of the standard magnesium sulphate...

 

[Marvo]

wish i new about that when i did a rod for a caravan on a beach , ended up installing it in a stream , worked a treat mind o.89 ohms enloced the connections and covered them with grease ,been tested 3 or 4 times since and the readings are stable

I've seen earth rods installed in small streams before (usually next to illegally installed pumps for farm irrigation) but the environmentalists have a hissy fit if they catch you doing it. If there was grease involved they'd probably have a prolapse of some sort, it's not good for the fish.

 

[Knobhead]

I've seen earth rods installed in small streams before (usually next to illegally installed pumps for farm irrigation) but the environmentalists have a hissy fit if they catch you doing it. If there was grease involved they'd probably have a prolapse of some sort, it's not good for the fish.

I’ve used a old mill race so the spikes were hidden behind the mill building so the Peak Park Planning Board couldn’t find them. The PPPB came sneaking around just as we were unloading the 45KVA generator. Took some quick thinking to get rid of them while the gen set was sat on the back of the wagon. How we hid the exhaust was ingenious, it went out through what remained of the mill wheel and was hidden in a small copse.

The stupid thing is I enquired about an 11KV OH line, OK by the PPPB but at £30K+ it was a non-starter. When we applied to install the generator that was turned down because of noise pollution.. With the supplementary silencer you couldn’t hear it running out side the mill. I made the supplementary silencer at work.