Electrical question

[Drunk Monkey]

Im.hearing conflicting advice so any CURRENT or retired sparkies out there ..
What size cable should be used fir the mains supply from.the lamp.post to the house .. i know it varies due to the distance , in this case the house cable entry point us very clise to the electric between post approx 6 to 8 m... just a normal single story home with the normal electrical set up and equipment

Thanks in advance fir any info

Dm

[noosard]

Dont be cheap
Use a big cable

[Bandung_Dero]

Up and down our road the feeder from the distribution cables down to the power meters is 6mm2 and in my case the cable from the meter to the house is 10mm2. About 30 meters in length.

Attached is a copy of AS3000 (Australian Standard) cable sizing guide as a reference.

[pal52]

Your Main circuit breaker is probably 50 amp so 10 mm copper cable will cover it.

[sometimewoodworker]

The question has just been asked of the Guru on electrical bits

Do check with the local PEA office but for a 15/45 meter on a reasonably short run (30m or so) 16mm2 copper or 25mm2 aluminium would be the stuff.

Is it running overhead or underground (different cable types needed).

Over ground aluminium or copper, underground only copper is approved unless you are the PEA/MEA

[Khun Paul]

Sorry ALUMINIUM is used by contractors when building as it is considerably cheaper. When I had a small problem over supply PEA duly turn up and decided that the Blue Aluminium feed from the Meter installed by a previous bod was breaking down and they NO LONGER considered Aluminium as a safe alternative.
They cut out the offending cable and using a black pure single core copper cable ( size unknown ) but I believe rated fairly high, to connect my meter to my house cable the same size as they were using . My breaker is 100 amp resettable, therefore I assume my cable can take that amperage. The temp max is 70 degrees C, on the cable so can be external as well as internal.
Ever since no voltage dropping and no blackouts apart from PEA maintenance

[tamada]

Per the guru, go with 16mm2 copper which I think is 6 awg in other countries.

That's what we used on our castle about 15 years ago. Ours is run in conduit down from 'lamp post' and along the wall in conduit to the main service breaker in a box on the wall outside. Thence into conduit down under house and back up into the CU, ie. it's ALL inside conduit. If you're dangling any wire in free air from the 'light pole' and up under the eaves in 'traditional' Thai sparky style, I believe that needs a different sort of wire, maybe the lighter aluminium stuff? Looks terrible anyway.

[Potamoi]

Use copper DM. AL has oxidation issues that you don't need to think about. The size should be specified by your electrical engineer when they designed the load plan in the consumer unit which you will need when you apply for service. I would wire it for 30 (100) A service is case you upgrade it later which would be 4awg or 25mm2. You may be able to get off cut lengths from a local shop rather than buying the whole roll from DoHome or whatever.

The attachment is apparently what you need to apply for service from PEA.

WMP234-6.pdf

(117.64 KiB) Downloaded 81 times

If you are sure you will never go above 15 (45) A service, 16mm2 will do.

Don't forget to plan for properly wired earth spikes (2 meter ones not the fake 30cm ones). Builders love to concrete over these but it is best to put a hole cover over the spike so you can inspect it from time to time and allow water to reach it.

[Drunk Monkey]

Many thanks to all ...

Pal52 ..looks like the main breaker is 100amp .. my builder is saying 10mm copper is ok ..im.not so sure .. it is o ly a short distance above ground to the pea post

Chz to all who offered advice

DM

[Potamoi]

DM, If your builder is saying 10mm2 for 100 amp service you may want to override his suggestion and buy the proper stuff.

You may want to go and talk to this shop near your location to confirm (by the 7/11 close to the airport):



Please note:

16mm2 = 9.1mm nominal overall diameter
25mm2 = 10.6mm nominal overall diameter

Is it possible he is speaking in mm nominal overall diameter rather than cross sectional area?

[Drunk Monkey]

ok cheers . i will delve deeper as in my CURRENT state im confused and SHOCKED...

btw how much is the proper stuff ?? per meter 16mm

DM

[sometimewoodworker]

In air the absolute minimum copper size is 16mm if you have 90C cable but 75C is cable more common so 25mm is the size.
If you go with aluminium then it will be 35mm cable.

All of these numbers will change (get bigger) if you decide to do anything but have the cable in free air.

Aluminium cable is only approved for use in free air for non PEA installation. It doesn’t matter what your installers say there are good reasons for this, the PEA can be sure that the relevant protocols are followed, they know that non certified installers often don’t follow the requirements or don’t even know what they are.

[andymu]

16mm minimum or preferably 25mm

[Potamoi]

btw how much is the proper stuff ?? per meter 16mm

I think I saw 208/meter for 16mm2 and 288/meter for 25mm2 at Thai Watsadu today... just a passing glance while I was buying some 2x1.5 offcuts so I may be mistaken.

[Drunk Monkey]

thanks again to all udonmapites who offered info .. i will buy 16mm not put the 10mm as advised by the builder ...

DM

[Khun Paul]

Wise decision and YOU buy it , then you KNOW what you have paid for . !!

[mak]

According to the Cable Selection Chart shown above you will need 25 mm2 for a 100 amp Main Breaker.

[sometimewoodworker]

According to the Cable Selection Chart shown above you will need 25 mm2 for a 100 amp Main Breaker.

You missed the option to use a higher rated insulation to enable a smaller size cable. There is also the point that DMs cable run is very short.

[Drunk Monkey]

According to the Cable Selection Chart shown above you will need 25 mm2 for a 100 amp Main Breaker.

You missed the option to use a higher rated insulation to enable a smaller size cable. There is also the point that DMs cable run is very short.

the post meter to the fuse box in the house is only 10m - 12m .. so need 25m ish ... the fuse box is an 18 bay Sneinder make with a 100amp main fuse , RCBO fuses in 9 including bathrooms kitchen and out doors .. normal fuses of the correct amps in the other 8 for lights sockets etc etc..all electric wires to sockets lights etc are to plan regulations.. except for the Stiebon water heater 6000w and electric oven n hot plate which was advised to use 4 or 6 size cable.. i will go with the 16mm for the main.

I dont do gas at all ..hate the stuff nearly killed me in 2007

thanks all.

DM

[mak]

You have to size your cable to accommodate the main breaker. DM did not specify what type of cable he will be using. No sense having a cable that will melt before the breaker trips.