Static caravan Ze

[Tom420]

I've been testing a static caravan installation. At the plastic meter box outside the 'van (which contains an RCD, 16A MCB, meter and 16A socket for the caravan) I get a Ze of 20 ohms and 13.5A PFC. The earth is through the incoming looped SWA of 2 x 2c 16sq.mm cables (crude TNS from the point of view of this caravan but probably TT for the site). The RCD trip times are all fine so all is well.

If I put the earth lead onto the galvanised angle iron which supports the plastic box instead, I get a Ze of 1.16 ohms, 199A PFC!
I'd be more comfortable if the caravan had its own earth rod but I'm not responsible for the system, I'm only here to test the caravan and that is all fine. I'm tempted to bond the angle iron anyway.

If it was up to me every caravan on the site would have its own earth rod.

What does anyone else reckon?

 

[radiohead]

Why bond something outside? It is not possible to create a zone of equal potential

 

[Tom420]

I'm only here to look at the caravan which has the earth imported through the SWA. Yes ideally I would interrogate the site owner and test at the origin. From driving round the site I can see a few (2 or 3 out of a hundred or so) caravans which have what look like 5/8" earth rods beside their meter boxes, the rest just have the looped 2x swa's. So I assume the site is TT but it's really not my remit as I'm only looking at one caravan at the moment.

.

 

[westward10]

I assume this is the same thread as this one. This thread closed please keep the same topic to one thread.

Ze and earthing of static caravan

I'm doing an EICR on a static caravan after being called on to fix to a couple of problems due to loose connections. It's all fine now within the installation in question but the earthing arrangement on the site is bothering me as it is relying on many multiple connections in steel armour...

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