3phase Upgrade / Solar / Wellington Region.

[mrpackethead]

Hi, I have got a project at early design stage for a rural property. Multiple buildings. I have some thoughts, and I'm sure that the collective brain power here, will provide some good advice.

Current situation is a single phase 60A supply that is connected to a building that will be demolished, ( it floods ). Due to the supply pole failing, a new TUD was installed in the street, and there was just enough time (litterally only a couple of days) to get a new 3x16mm+Screen cable run into the Tud and across the boundary. Saved many thousands of dollars. The 60A/phase was the max available, without a new transformer.

The customer wants to install ground mounted solar, potentially up to 45kw ( 60A/phase ). but starting with 15kW,

I am looking at various options for distribution/metering for the property. I was out for lunch, and just happened to walk past an EV charging station, and saw a pillar installed next to it, which has a meter. I thought that something like this could make for a good option for the metering and distribution on this property.

(1) A bit of hunting around, and I located it ( https://www.rdlnz.com/product/pillar-al850900-pill/ ). I'm not set on using that particular product, but something like it. Any other suggestions?

(2) I'm thinking of installing it just inside the property boundary, and by keeping it reasonably small, it remains permissible under the district plan. I'd sink the Galv frame into some concrete, with some well implemented conduit to make cable entry / exit easy. From here I would run cable to submains for each building, and also to the solar..

(3) While all in the same cabinet, part of the cabinet woudl be allocated for the 'generation' .. with the relevent disconnects etc.

(4) The WE* network metering requirements appear to require a pretty huge space to install the meter, if its 'residential'. The space required for 'non-residential' is much less. I need to verify this with them, ( page 18 https://www.wel.co.nz/media/evwg1any/ne ... b-2024.pdf ). minimum 500x650 seems huge for a single meter?

(5) To me it seems pretty clear that this will not meet the exception for a readily accessible main switch, if the switch was installed inside the cabinet ( and locked ).

( The exception to 2.9.1 provides guidance. )

"Exception: A main switch need not be located on a switchboard, or be readily accessible, where unauthorized operation may impair safety and the
electrical installation is—
(a) located on public land; and (b) associated with telephone cabinets, traffic control signals and street furniture, such as bus shelters and the like; and (c) otherwise controlled and protected, in accordance with the requirements of this Standard."

So, options I can see, are

(a) leave the box unlocked so you could get access to it. This probably is not all bad, its going to behind a fence on private property
(b) Install somekind of main switch on the outside?

Would love to hear your thoughts.

[mrpackethead]

THe inspector whos doing the final sign off, is happy for the meter, and Switch to be in the cabinet, and for it to be locked. That makes for thigns to be a lot easier!

[AlecK]

Just on the issue of access to main switch, correct that Exception does not apply.
For the Exception to apply, have to meet all three of the conditions ; and this doesn't meet either (i) o (which is defined 1.4.2)r (ii).

The purpose of Main switches is linked to the way the term is defined; which takes some working through.
Not defined on Act or ESRs, so just looking at"3000" - and no definition in 1.4.
But terms only get added to the definitions list if they are used in at least several places through the document.
Where they are used basically in one main clause, they can be defined in that clause.
Index has 8 entries, but all either for either 2.3.3 or 7.2.
7.2 is safety services, so start with 2.3.3.

para 1 ( bold type, therefore a fundamental requirement) tells us the function that's required: to control (each) supply into the installation.
Also sets a default location of "main switchboard"; and that is a defined term
( this time defined in ESR4, so this over-rides the definition on "3000"):
"means the switchboard that is used by the consumer to provide the greatest degree of control of the supply of electricity to that installation".

So that's the key: the consumer has to be able to use it.
This is why those meter isolators often found on screwed-shut meterboxes are not "main switches";
first they are not at "main switchboard, and second they can't be effectively used by the consumer to control the supply.

Your case is different; your pillar will be the MSB.
The accessibility requirements are in 2.3.3.3: "readily accessible" , which is defined 1.4.2.
A lock on the door is not an obstruction; so as long as the consumer has the key, it's up to them whether they lock it.

[mrpackethead]

Its installed,