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Hi all
Just wondering.... for those chargers that require an earth rod, is that additional or included in the installation price (or each installer different)?
Thanks
Alan
 

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Hi all
Just wondering.... for those chargers that require an earth rod, is that additional or included in the installation price (or each installer different)?
Thanks
Alan
Each quote should state what’s included in the price.
Just as different chargers are different prices, installation quotes are likely to include (or not include) different things.
So, expect each installer to be likely to be different and read carefully as to exactly what they are quoting to supply and provide in their quote
 

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Hi,
If you are getting a car charger installed then all components of that install should be included in the quote.
 

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Hi all
Just wondering.... for those chargers that require an earth rod, is that additional or included in the installation price (or each installer different)?
Thanks
Alan

Should be included in the quote normally. Many installers would rather charge for an open PEN fault connection box though, rather than fit an earth electrode. Not much in it, really, as an earth electrode and pit costs £40 to £50, plus around half an hour's labour to put in, and the open PEN fault part of the connection box costs around £100 or so over the top of one without.
 

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We were having groundworks done anyway to partly bury the cabling, so they did the earthing rod as part of that. i.e. Minimal labour overhead. Only took a few attempts to find a spot far enough away from the wall foundations to actually sink it.
 

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Hi all
Just wondering.... for those chargers that require an earth rod, is that additional or included in the installation price (or each installer different)?
Thanks
Alan
Wrong question.

It's a good idea for your own safety to get a job done to a decent standard and if that means paying for a earth rod ( including the site specific installation aspects), just pay. No reason to be pennies wise and pound foolish. By the way how much are you paying for your car over the duration of its lease, or its purchase cost.
 

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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.
 

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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.
 

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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.

Yes and no. There's no doubt that a decent TT installation provides the most reliable form of protection from an open PEN fault. It's always going to be safer to directly detect a PEN fault this way, than use an indirect sensing method. The IET position regarding the use of rods relates solely to the relatively small number of cases where the location of incoming services is not known, or where such a rod would be within the zone of influence of a conductive incoming service. Around here it's very rare to find any location where an earth electrode wouldn't be perfectly safe to use. Almost all the older houses already have one, or the remnants of one, anyway, left over from the time when all houses used to be TT.

Even on newer houses it's not often a problem, especially as gas and water have been using non-conductive pipes for many years now. It's not at all hard to find where services come in, either, as there is pretty much always some dead giveaways as to the runs, both from where they appear at the house and where things like water meters and stopcocks are in the road. Main problem areas seem to be older terraced houses, where the front gardens have been turned into parking spaces. It can be challenging to get a rod in safely and far enough away from older conductive service pipes.

I'm not convinced that the IET looked at the very broad range of houses across the UK when making their observations about the use of earth electrodes, neither do I think they even thought for one moment about the non-earth rod solutions that are available. Their view is also at odds with the increasing use of earth electrodes for any and every telecoms installation across the land. Every one of these roadside cabinets, fibre boxes, phone masts, etc has an earth electrode, usually a very good one, as the need for a very low value of Ra is much greater for this type of kit.
 

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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.
 

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Be sure to post the results on here.

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.
 

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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.
 

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What sort of ze range are you hoping to get?

Not sure, TBH. The place is a bit further up the valley from us, so probably not as good as here (I put a rod in for our garage supply and got an Ra of 24 ohms at the first go - happy days!). Condudisc reckon these things give better readings than rods, but I'm going to bash a rod in temporarily so I can check to see if that claim is true.

Looks easy enough to install, just dig a 650mm deep hole, drop it in, and backfill, leaving the wire just poking out through a bit of conduit. I think I can get it within maybe 150mm or so of one of the deck support posts, so will try and run the conduit up the back of that, to keep it neat and a bit better protected.
 

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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.
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.
 

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@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 than 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.
 

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@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.
 

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The thought of a condudisc makes me salivate.

The bugger is I still don't know how much they cost. This one came via the back door, as the client works for a big telecoms company, and they are trying them for their cabinet earth electrodes, instead of earth mats. The thing is obviously designed to be screwed to the base of a timber pole, as it comes with some big screws and washers that look like they are designed to screw into the bottom of an American size timber power pole. It's obviously an American made product, as everything from the language in the instructions to the gauge marked on the wire was American. If I have to guess then I think these things are designed to be screwed to the base of power poles to take the place of an earth mat, making it quicker and easier for the US equivalent of a PoleCat to fit both the pole and the earth electrode in one go. IIRC, the US system grounds the centre tap of their two phase LV distribution network, so these are probably the US equivalent of intermediates earthing the PEN that we have on our three phase LV network.
 

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They are around £100 i believe? Cant remember if that was before or after VAT, and think thats without the Conducrete.

They're best used if you are digging a trench already (pedestal units). Especially if you have a few units to install. We had one condudisc for 3 points (new dedicated DB).
 
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