caravan park tt system and earth rods

[Engineer54]

Thats right thats what I am saying too thats why it has be TT other wise any parallel earth path becomes the earth further down the line TT breaks the two systems

anyway roast lamb for dinner I;m of

?????? ...Huh! No-one's suggested using PME!!!! The whole site including the main incoming supply is TT, where did you get the PME from for god's sake?? lol!!!!

 

[topquark]

?????? ...Huh! No-one's suggested using PME!!!! The whole site including the main incoming supply is TT, where did you get the PME from for god's sake?? lol!!!!

I think what he's trying to say is that's why you can't use PME; because of the chance of loosing the neutral and the corresponding consequences. But that's not how I read his post the first time (it's not very clear). I, as you, thought he was suggesting that loosing the earth was the problem with PME

 

[GLENNSPARK]

I think what he's trying to say is that's why you can't use PME; because of the chance of loosing the neutral and the corresponding consequences. But that's not how I read his post the first time (it's not very clear). I, as you, thought he was suggesting that loosing the earth was the problem with PME

Same here what i think he`s on about is the PEN conductor.................

 

[Engineer54]

I think what he's trying to say is that's why you can't use PME; because of the chance of loosing the neutral and the corresponding consequences. But that's not how I read his post the first time (it's not very clear). I, as you, thought he was suggesting that loosing the earth was the problem with PME

Yeah, .... i just read it again, myself...lol!! Must be thinking too much about his Sunday lamb roast dinner to get his thoughts straight!!:whatchutalkingabout

 

[topquark]

@monkey, have a read of your post #27 again, and you'll see what's caused the confusion: http://www.electriciansforums.net/e...n-park-tt-system-earth-rods-3.html#post355788

 

[Deleted member 9648]

Having had this discussion with E54 before,we are never going to agree on TT systems...fair enough,but I would like to make two points.
1. If the OP was carrying out a PIR on the supply system the only consideration is whether the earthing system complies with bs7671....the fact that there is a preference for multiple rods is irrelevant,a single rod with an Ra below the required value will meet the requirements,and for the purpose of a PIR that is the only consideration.
2. What is the difference between a single point of earthing via an electrode.....and a single point of earthing via a DNO supplied earth?....they are both single points of earthing and thus just as likely to be lost.

 

[GLENNSPARK]

Having had this discussion with E54 before,we are never going to agree on TT systems...fair enough,but I would like to make two points.
1. If the OP was carrying out a PIR on the supply system the only consideration is whether the earthing system complies with bs7671....the fact that there is a preference for multiple rods is irrelevant,a single rod with an Ra below the required value will meet the requirements,and for the purpose of a PIR that is the only consideration.
2. What is the difference between a single point of earthing via an electrode.....and a single point of earthing via a DNO supplied earth?....they are both single points of earthing and thus just as likely to be lost.

so on that basis then lets assume its a new install job......Multiple rod system or single?............

 

[topquark]

Agreed, that was what was trying to be uncovered, whether it was indeed the Ra of the rod leading to that low value, or "other extraneous factors".

Not a lot of difference, IMHO I think the main difference would be down to environment. If you've seen what goes on at a lot of these sites, vans moved on off, with very little room for manouver. Tourers in/out on a regular basis (often driven by Reginald Molehusband (ficticious name incase that causes offence) ). Large ride on lawnmowers.

 

[topquark]

so on that basis then lets assume its a new install job......Multiple rod system or single?............

Good question, can I vote for TNS please ... Multiple for me.

 

[GLENNSPARK]

I would go for a multiple rod system (1 deep rod for 4 caravans) as eng says. Deep rod for stability. This should give you better discrimination and as you say TQ, less likely to suffer ground disturbance as a result of heavy towing equipment, latrine diggers or whatever going round plowing up your nice cables..lol...
Downside to this: Increased cost due to time and materials.....I guess its a ballancing act this one......