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Posted By Topic: Caravan EWOF issues

Feb 12 2014 13:06

One of my employees, an electrical inspector, is having major issues with Caravan Electrical WOF\'s that he is completing and failing for various reasons.

It seems there are a number of electrical inspectors who will pass anything in this area which is undermining my inspectors work.

I would like some clarification on some key points:

1. If the caravan has no Earth-Neutral link, does it need to have one installed (or an RCD put in)?

2. If a switchboard in a caravan is metal and it is not earthed, is this a reason to fail an electrical WOF?
3. If the supply lead for the caravan is not provided, can the wof be passed (I would have thought that the supply lead is a crucial part of the testing also)?
4. If wiring in the caravan has exposed insulation, is this an issue that would stop a WOF being issued?

Thanks in advance for your thoughts!

Feb 12 2014 14:14

Good to see that your man is following the rules.

1 AS/NZS3001:2008 section 3.3.5 is the answer to this question but basically either the E-N link or an RCD must be fitted.
2 yes section calls AS/NZS3000 section 5 which deal with earthing. I agree with your inspector and would fail an unearthed metal switchboard.

3 no supply lead = no WOEF in my book. AS/NZS3000:2008 section C6 includes the supply lead in the inspection of the installation.

4 once again section C6.3 covers this.

Keep up the good work and support your inspector as he is 100% correct in his application of the standard.


Feb 12 2014 14:22

Thank you very much for your reply. I have read the standard and agree with everything you have said but really wanted some support from others in the industry.

It is so disappointing that there are others out there undermining the work of good inspectors. And nothing can really be done about it (unless you report the dodgy inspectors which I am not a big fan of). Does anyone else have any thoughts as to my questions above?

Feb 12 2014 15:10

The rules for issue of WoEF have changed several times in recent years, most crucially with the adoption of Amendment A (NZ-only) and now Amendment 1, which was to have incorporated Amdt A but ended up a bit different because Amdt A had a significant safety flaw.

So for a while it was valid to issue a WoEF with neither RCD not N/E link, but now that Amdt 1 has been cited in ESRs this is no longer the case.

Ignore section 3, it is not relevant to issue of WoEF. App C, specifically C6 & C7, is the bible for that.

And right now App C says:

1 C 6.9 (d)
if any final subcircuit does not have RCD protection, there must be an N/E link
(this is the bit where the flaw in Amdt A crept in, due to poor wording).

2 C 7.5 (b)
a metal switchboard enclosure must be earthed

3 C 6.7, C 6.8, C 7.3, C 7.5
Each of these means a WoEF cannot be issued in absence of a supply lead.

4 C 6.3
Exposed basic insulation of live parts = fail.

Feb 12 2014 15:33

Thanks for that. I have once again been caught out by having an older version of the standard (did not have Ammendment A) which was adding to my confusion with regard the N/E link (clearly they made a mistake which they corrected in the last ammendment).

Is a good reminder to look up and download the latest versions of standards regularly!!!

Feb 12 2014 16:07

not always necessary to have the latest.

What you MUST have is whatever flavour is cited in ESRs.

It\'s a good idea to write on the cover the date it applies in NZ from (ie date that Regulation citing it comes into effect); and date when a later version is cited.

But never throw any of the old ones away, as sometimes you need to know what rules applied at a particular date.

off top of head I can\'t recall when Amendment A to 3001 came in, would have been 2011 or 2012 ESRs amendment. But regardless, it\'s only historic now, superceded by Amdt 1.

What it tried to do was to allow N/E links to be removed, so that old caravans could plug into new caravan park sites (which have RCD protection. emoval is PEW, and that work needs to be certified. Amdt A also brought in a requirement that when any PEW was done on a transportable, a FULL set of earth continuity tests has to be done - including all the bits that weren\'t ouched as part of the work done. Older linked caravans often have the incoming E on the N bar, so removing the link can mean nothing is earthed.

App C was changed so that a WoEF could be issued with no link present. But the way that was done, just deleting item (d) of C 6.9 left a potentially dangerous loophole. Amdt 1 brings back (d), and with it the \"either / or\" bit, so that there must be either a link or RCD protection for all subcircuits.
It also forces installation of RCD when any alteration is made to the installation 9including link removal)

So now it\'s OK to remove a link, provided you do the earth testingand install an RCD.

Some links will still be removed without the RCD going in (or the testing), but they\'ll be caught at next WoEF check.