New Electrical Connection

[uidaa]

G'day all,

I’ve just finished electrician A-grade. Someone is built the new 2 house (front and back) and asked me for information as they will supply parts and I’ll do the work. Since I’ve got hand over from my master as he is oversea for 5 months holiday, he will approve when he’s back. I’ve asked around but still need some advice. This is how I would do:
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For back house, 3-phase underground cable from the Pit to the electrical meter is 5 meter, so SDI cable would be 16mm2; 3 x 7meters of white-red SDI cable and 7 meter of white-black SDI cable. Front house, 240V 2 x 7m white-red and white-black cable. Is this correct? Can I make a loop before the supply meter to save front house cable? These will run under 2 x 70mm orange conduit, 600mm deep for 2 houses,
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Front house, from electrical meter to switchboard is 20m, same SDI 16mm2 cable, so 2x20 m white-red and white-black cable. Back house is 40m, so 3x40m white-red and 40m white-black SDI cable. Still run with 70mm orange conduit. Can I use 3-phase PCV orange cable, 4core and earth 10mm2 for the back house?
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If I run out of white-black SDI cable, can I use white-red SDI cable instead?

Should cable insert into conduit then put underground OR conduit first then pull cable later? I will ask someone to inspect the conduit before fill the soil.
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Back house, they will have 1 small (2.5kW) and 1 big (7.1kW) air conditioning, can I use 2.5mm2 cable to connect or has to be 4mm2, 1 phase each connection?
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Front house is ok as only 1 phase, but back house is a bit complicate. Do you have any ideas; suggest how to connect to CB for equivalent balance?
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Many thanks.

[NCArcher]

Since you've just finished electrician A-grade, refer to your AS3000 and AS3008 for all the answers you require. Well done on completing your A-grade. I'm sure your 'Master' will be able to help you with anything else when he gets back.

[tricky4000]

Not a sparky myself so I would be worried if this were my place you were wiring up. Shouldn't you already know this stuff?

[uidaa]

Thanks for your reply.
There shouldn't be any connection yet, only for installation. Just want to make sure i'm doing the right thing, improve my knowledge and more confident when deal with 415V.

[echnidna]

No, all standards are fluid and ever changing, so you need to keep to update regularly

[patty]

is this strata title ?Have you calculated Voltage Drop on these runs and Max Demand?? Why are you using SDI I only ever use XLPE on Underground mains?
Are you going to run the Mains to a designated metering location and run Another set of Submains to the other house and have it on another seperate meter?

[Pheonix]

Put him on your must miss list

[mxchris69]

in nsw a new rule came out in november you can't use sdi only xlpe for mains. why im not sure but sdi has been fine for all these years that it has been used

[uidaa]

I’ve been told to use SDI cable in years and XLPE is so strange to me.
The Main meter to switch board of each house will be the same cable from the pit to main meter. I’ve calculated the voltage drop and 10mm2 PVC, orange cables seemed to be ok too. Those cable will be in orange conduit anyway. Why can’t I use that?

[patty]

O'h Dear I would be doing 2 things if I were you, otherwise you will be wasting your customer and yourself time and Money!!

From the Info Supplied you are fresh out of the trade and really have never done any domestic work fullstop!.....I doubt very much you hold a contractors Lic,Business Name or Insurance's


Your Options are

1/wait for your Master to return and if he is the Master He should know what to do
2/Or Consult your local Energy Authority Inspector for more detailed info and most likely a grilling!!!!

[nev25]

Can I make a loop before the supply meter to save front house cable? These will run under 2 x 70mm orange conduit, 600mm deep for 2 houses,
<O

As an A grade you should know this 600mm is wrong

Can I use 3-phase PCV orange cable, 4core and earth 10mm2 for the back house?
<O
If I run out of white-black SDI cable, can I use white-red SDI cable instead?

As3000 will tell you this

Back house, they will have 1 small (2.5kW) and 1 big (7.1kW) air conditioning, can I use 2.5mm2 cable to connect or has to be 4mm2, 1 phase each connection?

Gee this is first year trade school stuff
<O

Front house is ok as only 1 phase, but back house is a bit complicate. Do you have any ideas; suggest how to connect to CB for equivalent balance?
<O

now I'm confused

Mate as patty said

1/wait for your Master to return and if he is the Master He should know what to do
2/Or Consult your local Energy Authority Inspector for more detailed info and most likely a grilling!!!!

The question I ask is who is signing the compliance certificate.
An inspector will need to sign it and the supply authority wont put supply on unless its on site and have a copy

Then theres the question of Insurance what happens if things go wrong .

Im doubting if the supply authority will even bother turning up unless there is REC on site.

Ring a local inspector for guidance
After all he has to approve the work.