Each quote should state what’s included in the price.
Earth rods are no longer recommended by the IET anymore, unless there is certainty about the utilities running beneath the installation.
That said, the installer should know what their intended installation plan is.
Be sure to post the results on here.As an alternative, I'm going to be putting in a different type of earth electrode in a couple of weeks time, as an experiment, really. It's not a charge point, but a badly installed hot tub, that some pratt has installed without regard to the MI's that clearly state that it needs an earth electrode or other form of open PEN fault protection (for exactly the same reasons as a charge point does). I've persuaded the owner to try a Condudisc, as overall the cost is pretty much the same as a rod and pit, but it's a bit neater looking, as there's no pit or connection box needed. The disc just gets buried in a hole and covered over, with the (protected) conductor being completely hidden and running up into the connection box. In this case the connection box is on a post that's part of the decking surrounding the tub, so the plan is to install the Condudisc right next to the decking and run the wire up to a new connection box with an RCD.
Not used one of these before, but have used very similar conductive concrete once or twice, with an embedded copper strap as the electrode. I'm expecting the Condudisc to work at least as well as that, but plan on taking a normal earth electrode rod along as well and doing a comparison between the two, to see if there's any difference. The Condudisc may have some advantages for charge point installations, for example there's no risk of accidentally hitting something below ground, it may be easier to install in rocky ground and, as there's no need for a pit or box it may well look a lot neater if it's somewhere like the front of a house.
Be sure to post the results on here.
I thought there was talk of an amendment to start using the iron in the foundations as an earth on new builds. Interesting how everything goes full circle.Wilco, I'm really curious to see how easy these things are to install, and what sort of value of Ra they give. They do say that the resistance decreases gradually over the first few weeks after installation, so I may try and pop back and check to see if this is the case.
I thought there was talk of an amendment to start using the iron in the foundations as an earth on new builds. Interesting how everything goes full circle.
What sort of ze range are you hoping to get?
We installed one of these on a commercial ev point install a few months back as we had to dig a trench to the car park. Can fully recommend, we emailed the supply company (earthing solutions??), they check the install site address via a database for expected results and can usually recommend a size disc and how many bags of conducrete to use. We used 2 bags of conducrete and got a good Ra, ill try and post our results when im next in the office. Very easy to install, civils guy and client (electrical firm) were very impressed.Wilco, I'm really curious to see how easy these things are to install, and what sort of value of Ra they give. They do say that the resistance decreases gradually over the first few weeks after installation, so I may try and pop back and check to see if this is the case.
The thought of a condudisc makes me salivate.@NeavesElectric and @Robinsond22000 ,
Just got back from digging a hole in the rain. . .
Installing the Condudisc was pretty easy, cut a square of turf off and put it to one side, dug a hole with a mix of a hand held post auger and one of those post hole shovel things, put some flexicon over the wire as additional protection (although it's pretty hefty) and then backfilled the hole with soil, packed down hard around the disc. The thing is heavier than I expected, TBH, although an easy enough one-man job. Managed to hide the flexicon up behind one of the decking support posts and lead it directly into the RCD enclosure, as the Condudisc had around a couple of metres of cable.
I also banged a rod in across the other side of the hot tub decking, just to see how the two compared. Being a wet day, these results will be about as low as they are likely to ever be, so I'll go back and check again next time we have a longish dry spell. The Condudisc tested out with a Ra of 33Ω, the rod had an Ra of 47Ω.
All told I was pretty impressed, as I opted to just bury it in the ground with no conductive concrete, really because I know that the ground around here always gives pretty good readings with just a single rod. Apparently, Ra should reduce slightly after the Condudisc has been installed for a time, be interesting to see if it does for real. Hardest part of the job was digging the hole, but, TBH, it was less work overall that digging a hole and making good after putting in an earth pit, so nothing in it, really, especially as for a job like this it was just a matter of getting the original bit of turf back in place neatly. The really big advantage is not having to go very deep, in most cases the thing will be above any plastic water or gas pipes coming in, as they should really be a another couple of hundred mm further down.
The thought of a condudisc makes me salivate.