uksparks
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you should be able to see if it is PME without calling them.
I wont help even if it's not anyway.
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you should be able to see if it is PME without calling them.
Not the same. No.
i like the idea but there just isn't the option to do this unfortunately due to it being a car park immediately outside the building.
I seem to think this is going to be more problematic than planned for.
i think other than connecting the rod to the met there's probably not a lot of choice.
I seem to think this is going to be more problematic than planned for.
Not to the MET. The rod would earth the VCP only.
Not to the MET. The rod would earth the VCP only.
Why not? It'll be much better for the installation as a whole to have a decent earth nest connected to the MET than it will to have what is effectively a big external socket connected to its own earthing reference in such close proximity to the metal building bonded to the PME earth.
I guess I could put a rod or two in the base of the unit as looking at it, I'll be able to do this quite nicely, make connecting it easy.
I guess I could put a rod or two in the base of the unit as looking at it, I'll be able to do this quite nicely, make connecting it easy.
I cannot answer that TBH. Just does not sound right.
I'm so I'll just run 16mm swa to the charge point, connect it to the met, and also connect an earth rod in for good measure.
Ok so we have a plan of action, it says in point two, a rod of very low resistance. Can anyone telld what if says in 722 of the regs as have not got a BYB yet.
I always start with 2off 8'x5/8" rods spaced 10' apart and then test that and work up from there.
The earth electrode(s) should be connected back to the MET, not to the end of your new circuit.
Why doesn't it sound right? Adding an extra earth electrode to the PME supply is only going to improve it and make your installation safer in the event of an external neutral fault. This is exactly what is recommended in the regulations for swimming pools fed via a PME supply and is required practice for PME supplies in other parts of the world.
I always start with 2off 8'x5/8" rods spaced 10' apart and then test that and work up from there.
The earth electrode(s) should be connected back to the MET, not to the end of your new circuit.
Wont the fault then take the path with least resistance which is bound to be the PME earth which pretty much makes the earth rod pointless?
It just does not. I am not dismissing you or belittle your post. I am all ears and would like to understand more. I would have though somewhere in BS7671 it would say something like to earthing systems cannot be in one location. Guess guess guess. Not fact!!!!
don't get many swimming pools on the railways although the unions are thinking about this 'right' in there current talks.
If the Rods can achieve around sub ohm Ra they will be effective, also the way I read it they are as backup in case of a broken DNO Neutral to keep Ut low.
Wont the fault then take the path with least resistance which is bound to be the PME earth which pretty much makes the earth rod pointless?
You aren't mixing earthing systems.
A PME supply has an earth rod connected at regular intervals from the substation right up to the end of the cable run. All you are doing is adding another electrode which is connected at the MET of the installation. The big danger with PME is when the neutral becomes broken between your installation and the DNOs earth rods, having your own rod connected to your installation mitigates the danger in your installation.
Wont the fault then take the path with least resistance which is bound to be the PME earth which pretty much makes the earth rod pointless?
Ill have to go back and dig a hole to see whats there, I will not be able to just leave this and turn up on the day to do the job.
So are you saying connect the rod to the end of the circuit yes?
Not to the MET. The rod would earth the VCP only.
Why doesn't it sound right? Adding an extra earth electrode to the PME supply is only going to improve it and make your installation safer in the event of an external neutral fault. This is exactly what is recommended in the regulations for swimming pools fed via a PME supply and is required practice for PME supplies in other parts of the world.
no connect the rod to the main earthing terminal not at the end of the circuit
I have no reason to disbelieve what these guys are saying with regards to earth ridding to the MET.
So are you saying connect the rod to the end of the circuit yes?
You say not to the MET...
You say at the end of the circuit.
You say to the MET
You are now saying to the MET.
Which is it??
I didn't say the end of the circuit, or if I did it was a mistake.
Can I not connect it to the armouring to take it back to the MET or the CPC of the circuit? Do I have to run in another 10mm earth, I then have the hassle of protecting the earth cable when it leaves the wall and into the ground...
I thought you were going 16mm^ now ?
I hear you all. I just cannot believe this is not a standard practice. Seems like sense in all PME supplies.
I thought you were going 16mm^ now ?
all this hassle for charging a toy car. :icon6:
Can I not connect it to the armouring to take it back to the MET or the CPC of the circuit? Do I have to run in another 10mm earth, I then have the hassle of protecting the earth cable when it leaves the wall and into the ground...
what about connecting to the rebar in the reinforced concrete base?
It is up to you, I have presented my reasoning for connecting it directly back to the MET. If you think this is wrong or whatever then you don't have to follow it.
Sorry I don't know why I said 10mm, hang about, would it have to be 16mm as its strictly speaking a main earthing conductor.
You say not to the MET...
You say at the end of the circuit.
You say to the MET
You are now saying to the MET.
Which is it??
Dave mentioned that way way back lol
Me personally right now would earth at the end of the circuit. BUT, Wednesday when I am in the office I am going to look at what the other guys said, compare this to what I can find in the BYB and make a decision about how I would do it in the future.
Remember. YOU need to be happy that it complies.
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