Ze on campsite

[tombennetts]

Hi all.
Currently working on a campsite installing new hook up points. Just had a new 3 phase supply installed. Each phase feeds a separate consumer unit which in turn feeds 4double hook up points each. The supply is tncs up to the hook ups (protecting the swa) and tt at the hook ups. The ze at the hook ups varies from 240 ohms to 790 on one earth rod. Anyone got any good ideas on lowering the ze, as at the moment the rcd's aren't operating due to the high earth path I'm assuming!
Thanks
Tom

 

[tombennetts]

armoureds from the 3 phase metal clad board are all terminated properly, none of that bonding clamp strapped to the armoured rubbish! They then run to the single phase consumer units (plastic) which have the earths of the armoured all linked. The armoureds then run on to the hook ups (plastic) where the glands are termnated and earth is not connected to the hook up.

 

[NMc]

Two options to seperate the TNCS

Option 1: Separation of caravan pitch TTearthing arrangement from distributor’s PME earthing facility at consumersdistribution position

Option 2: Separation of caravan pitch TT earthing arrangement from distributor’s PME earthing facility at pitch supply position

 

[tombennetts]

option 2 is the route i have taken, so i think i will stick with that and get the hammer out for some more rods, or get the farmer digging out for some mats!

 

[topquark]

option 2 is the route i have taken, so i think i will stick with that and get the hammer out for some more rods, or get the farmer digging out for some mats!

Might be worth asking him if the field has been dug over recently, if it has then may be better to go deeper rather than more rods.

 

[tombennetts]

im pretty sure its not been dug. they know it get rockier as you move further down which fits in with our rising Ze values. Might have to replace the rods as the ones used are the thin ones you cant attach to.

 

[NMc]

try screw on rods and drive deeper in ground

 

[nickblake]

What you could do is install a rod near a roof down spout , put an earth rod pit in and direct some of the water over this area this way the area will be kept moist or better still a sink outlet hand was type not food sink this will then keep the ground wet in dry conditions then the readings should be lower realy it all depends what the ground is mad of soil clay sand etc i had a caravan supply on a sand dune only way i could get the readins low was to install a rod in a nearby stream was well low then

 

[tombennetts]

i know what im doing tomorrow then, hitting my hand repeatedly and hopefully every now and then i will get the rod!

 

[tombennetts]

no streams, no downpipes, the field is pretty remote from buildings. May be able to get to the water standing pipe though.

 

[topquark]

What you could do is install a rod near a roof down spout , put an earth rod pit in and direct some of the water over this area this way the area will be kept moist or better still a sink outlet hand was type not food sink this will then keep the ground wet in dry conditions then the readings should be lower realy it all depends what the ground is mad of soil clay sand etc i had a caravan supply on a sand dune only way i could get the readins low was to install a rod in a nearby stream was well low then

In the showers?

 

[NMc]

Do the job right. cowboys P on rods

 

[tombennetts]

i did consider that but the campsite is getting busy and i get stage fright.

 

[NMc]

You sign the cert

 

[yellowvanman]

Heard a story once that someone setup his sprinkler to turn on once a day to water his earth rod!

 

[tombennetts]

sorted out today, down to 70 ohms. cheers guys