Earth rod fluid

[Deleted account]

Some where on this forum a while ago someone mentioned poring a special fluid (not urine) or resin down a hole by earth rod to improve surface area connection to the mass of earth in high resistance areas.

What is this fluid/ resin called.

I need to earth a new supply on. Very stoney, shale type ground. A 3 meter trench has been dug on site and the shale earth goes all the way.

 

[Deleted account]

At your point of connection like any other electrode. The only other way to interfere with the cable is to dig it up.

Or cut it.

I like the idea strima and I am going to go for it with the addition of actually connecting part of the stripped back 16mm cable at the insulated end to a 1meter rod shoved in the ground. This way I get that safety connection notice I’m concerned about and earthed by rod and earthed by 16 mm cable surounded by marconite resin.
Cheers.

 

[Robson689]

Please don't pay £100 for a bag of marconite!! If you're anywhere near Whiltshire you can get it from Telkom for about £30 a bag or have courier delivery. Just will need to buy some cement but certainly beats paying 100 quid.

If you're backfilling a rod with it make sure you make it sloppy and widen the hole with the rod if possible for each one you drive on top

 

[Strima]

Or cut it.

I like the idea strima and I am going to go for it with the addition of actually connecting part of the stripped back 16mm cable at the insulated end to a 1meter rod shoved in the ground. This way I get that safety connection notice I’m concerned about and earthed by rod and earthed by 16 mm cable surounded by marconite resin.
Cheers.

Why so concerned about a label? If buried place a strip of electrical warning tape above it as recommended in several publications. If someone wants to cut a cable then a label won’t stop them.

 

[davesparks]

If you've already got an open trench there that's deep enough then join some earth rods tigether and lay them in it horizontally. Add conductive cement and voila!

 

[Deleted account]

If you've already got an open trench there that's deep enough then join some earth rods tigether and lay them in it horizontally. Add conductive cement and voila!

Unfortunately it’s the start of some foundations for new building.

 

[davesparks]

Unfortunately it’s the start of some foundations for new building.

Even better, metal buried in regular concrete works as an earth electrode. As long as the connection to it is suitable for burial it will do the job fine. Connect to any reinforcing that goes in the foundations if you can.
A particular type of earth electrode, known as ufer earthing, basically uses mesh in a concrete slab as the earth electrode.

 

[Carl S]

You should be looking at an Ufer earth if the footings haven’t been poured yet.

A bare earth peripheral conductor laid alongside drains works very well, no need for rods.

 

[Marvo]

Unfortunately it’s the start of some foundations for new building.

If they're using steel rebar in the foundations bolt a lug onto that and connect it using a bare copper conductor along with your rods and wire/mat. The more the merrier.

 

[bill01803]

FYI the minimum csa for buried bare copper is 25mm

 

[Deleted account]

Quick update.

Did the job partly as strima advised.

2.4 M rod 5/8 with 16mm earth connected and an extra 6M stripped back and buried at bottom of trench.
Marconite poured into bottom of trench around 16 mm stripped earth as trench filled more Marconite surrounded the rod.

Achieved 69.1 ohms Zs

Next plot over asked me to check there install as there spark said it had only just passed. Out of curiosity I did Zs it was 195 ohms.

I would normally not be happy with 69 ohms but considering the slate and stone type ground I am quite pleased with result.

Thanks for advice guys.

 

[Strima]

I'd be happy with that.