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Posted By Topic: ESR 74 - 6 months isolated CoV requirements

Sep 17 2019 17:42


I have a couple of questions I would like to clarify please WRT ESR 74

This regulation applies to a low voltage installation or part installation—
that has been disconnected or isolated from a power supply; and

Does the above include smart meter disconnections? Not an electrical disconnect and arguably an isolation?

If the period since the last disconnection or isolation of the installation or part installation is more than 6 months, the person proposing to reconnect or restore supply must,

"Proposing" - must one get on ones knee before reconnecting / relivening? Seriously who proposes to reliven? The retailer? The person reinserting a pole / pillar fuse? Why is the word proposing in there?



Sep 17 2019 19:18

Yes it includes "smartmeter disconnections". It applies whether disconnected or isolated.

"propose" is just a word which means "put forward (a plan or suggestion) for consideration by others".

The person doing the reconnect or restore can do the certification themselves. Generally it just comes down to getting the customer to agree that it's required and needs to be paid for.

Sep 17 2019 19:31

Thanks Doug. I guess my question is - whos responsibility is it? I was under the believe the onus was on the person pluging the fuse back in (or conencting the wires or clicking the mouse from remote) but the word "proposing" may suggest it is someone earlier in the command chain than this?

Sep 17 2019 20:02

Yes, the person putting in the fuse, or doing the remote reconnection, must sight the certificate, or COC is work has been done.

If it's going to the power company and there has been work done, then it is ESR73A that applies.

I would write on the COC that "This certificate complies with the Electrical (Safety) Regulations 2010, regulation 73A, for re-connection of supply"

Sep 17 2019 22:19

i had one done a few weeks ago, they relivened remotely but they also had someone on site checking polarity etc. in prepping for it i found a high resistance in the lines nuetral and lots of current going through water pipes on the shopping centre. lucky i had my wits about me when testing as others might have got hooked up thinking it the whole place was dead without a phase feed....

Sep 17 2019 22:54

Apropos the OP: I havent come across that situation before (except for perhaps on old 1940s neutral bar). You could add another bar to it with a bolt and double nut connection.

A nicely stripped 6 mm wire (not twisted) will surprisingly fit into a lot of tight holes.

Sep 17 2019 22:55

Whoops, wrong thread.


Sep 18 2019 09:05

The "isolation" by smart meter may not be isolation at all. Does the meter's internal switching have an isolation rating? Does it comply with Clause "3000"? If not, it ain't an isolating switch and operating it is not isolation - just functional switching. Which is all any retailer wants.

And of course the answer is that it's a switching device that can't be secured in the open position; so it does NOT comply with, so it's NOT isolation. And if you are doing PEW, you're supposed to have isolated, so you can't rely on this meter's functional switching.

It's certainly not "disconnection".

Have to be careful with that word. Retailers & networks use "disconnect" & reconnect" for actions that are not disconnection / connection for purposes of ESR 73A . As do installation Standards, eg fault protection & RCD rules talk about "disconnection". But For ESRs, these words have a special meaning that's explained in 73A(5). And I believe that meaning carries across to ESR 74 also.

Since the switching-off by smart meter isn't isolation, then switching on isn't re-livening / re-connection; so ESR 74 doesn't kick in. for purposes of ESRs, the installation has remains livened throughout. same as a light is still livened, and the N to it is a live conductor, as long as the active hasn't been isolated. Functional switching does NOT make safe.

Also ESR 74 ONLY applies if NO general / highrisk PEW has been done during the period of disconnection / isolation. Therefore a CoC is NOT going to be involved.

If the period is shorter than 6 months, NO paperwork is required at all.

If the period is longer than 6 months, you need the certificate specified in 74(2); which used to be called a CoV, but that term was dropped with intro of ESRs in 2010. Ideally would include words reflecting those in the ESR. Something like:
"I have checked the [ID of installation] in accordance with section 3 of AS/NZS 3019; and certify that it is suitable for continued use"; date/signature/name/reg.

As DougP said, if general / high risk PEW has been done; then ESR 74 does NOT apply, but 73A does instead. In which case there WILL be at least a CoC, and we're definitely using that special meaning of "connection" - and operating a smart meter by remote isn't "connecting".
There will be someone on site doing actual PEW that makes an actual physical connection (never mind enlivening, that's different). That's who has to do the pre-connection checks; that's who has to sight any CoCs & RoIs, and that's who must issue the ESC.

Exactly who that is depends on exactly what work is done, and in what order. But EVERYONE who connects ANYTHING to a supply of electricity (as against connecting to something that is itself still fully isolated) has to go though all the requirements of ESR 73A, including issue an ESC that covers EVERYTHING downstream of where they made the connection. I.E. EVERYTHING that could become live after connection but not before.


Sep 18 2019 11:20

Hi Alek.

Is using the Standards to define terms used in regulations (a higher document) appropriate (isolation)? I have been challenged on this point in the past.

Meter Retailer and Meter owner is separate. Meter retailer asks meter owner to restore supply - not flagging > 6 months delivened (ignoring the term isolate for a moment). Meter owner presses the button - meter is live. A third party discovers the supply has been relivened without the appropriate checks (ESR 74). Meter owner saying it wasnt us that "proposed" the relivening. Meter retailer saying "we didnt press the button".

My interpretation is both were proposing to close a switch (using the dictionary definition of proposing) and both have fallen foul of ESR 74. However 74(4) only makes the person that did the job (not the person proposing to do the job) liable of L2 penalty.

Is my interpretation correct?

Sep 18 2019 11:47

Correct definitions in EZRs / act over-ride those in Standards - including for terms used in Standards.

But "isolate" is not defined in either Act or ESRs, and ESR 4(3) tells us that therefore we use the meaning from "3000"
Also, the metering is part of the installation, and therefore is required to be installed i.a.w '3000"; so requirements for devices for isolation apply.

All a smart meter can be is a functional switch, NOT an isolating device.

"disconnection" is also not defined in either act or ESRs, except "for the purposes of this regulation" in ESR 73A. So again the meaning comes from "3000" (for installations).
Even if the term is not specifically defined, the meaning is what comes across an is applied to ESRs.

So; taking that special meaning of 'connect" as only applying to ESR 73A, and doesn't carry across to ESR 74 (as I believe it should); then disconnect / isolate in ESR 74 take the meanings from "3000".
In that case, the smart meter can't isolate, but can disconnect.

The person proposing to reconnect is whoever is going to operate the device, in the case of a smart meter that may be remote operation.

For old-fashioned installations, whoever is going to place the supply fuse.

So for your scenario, the person pushing the remote button (or clicking their mouse)is the one who does the re-livening; and therefore must sight a certificate if the installation has been de-energised for > 6 months.
Which is the ONLY required check; though might be wise to seek a "no work" declaration from the owner.

ONLY the individual person operating the switch is responsible; the energy trader asking for it to be done isn't proposing to re-enegise, they're just making a request. Proposing that it be re-energised, if you like; but not proposing to actually do the re-energising. The person doing the switching has the choice whether to re-energise or not, and is the ONLY person who can do so. Accordingly only that individual can get in trouble if they fail to sight the cert before operating their switch control.

Note that this Reg also applies to part-installations; something many seem to ignore.


Sep 18 2019 21:31

Thanks Alek - this was my take on it as well however I was being challenged by a "mouse clicker". Its always good to get a second view to ensure I'm not missing something.

Yes I had noted the part installations bit as well, and agree with your sentence.

Sep 19 2019 09:07

In my experience, very few people in positions such as your "mouse-clicker" have any understanding of how the ESRs work. Or even of what individual ESRs actually say.
They're generally driven by motives other than compliance; mainly avoidance of responsibility for their actions.

There's also been a big push recently by a major metering installer to try to have energy traders accept responsibility for undertaking ESR 73A pre-connection checks, including sighting CoCs *& RoI, when the connections are actually being made by the meter installer's own employees (who are mostly non-licenced).