How to wire a house using 3 phase

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doggy
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We are getting 3 phase power delivered to our property via our own dedicated transformer. We want to rewire the house and other buildings so that we can use different appliances on different phases. We have 4 air conditioners, 3 hot water units and the usual assortment of things you would find in a house. The other buildings have a similar setup.

It seems to make sense to split the hot water units across each phase and to do something similar with the air conditioners.

But the big question is what sort of distribution unit do I need to achieve this? It will have 3 phase power going in and then it needs to supply single phase circuit breakers that may each be connected to one of the three phases.

We also want the system to be protected by an RCD.

Is this doable?
 
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Yes, it's probably doable. But it does depend on the details.

Your next, AND ONLY GOOD CHOICE, is to hire an electrician. This falls into the category: if you have to ask the question, you don't have the knowledge to do it yourself.
 
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Hey, hiring an electrician is definitely a way to go, but we still can give some advice as to what is considered a good practice. OP never said they want DIY, they want to learn - even if only to understand what the hired electrician is saying :wink:

One thing for sure: if you plan on having any kind of computer network with computers/routers/whatevers connected by ethernet cables, they should be all connected to the same phase.
 
DaveE said:
Yes, it's probably doable. But it does depend on the details.
Doable kinda. The problem is there is no 3--phase standard for residential wiring. There is no standard plug or amperage. Every circuit needs to be individually designed and wired for the specific piece of equipment it is powering.

DaveE said:
Your next, AND ONLY GOOD CHOICE, is to hire an electrician. This falls into the category: if you have to ask the question, you don't have the knowledge to do it yourself.
Or maybe an engineer before the electrician. Codes say that a certain amount of electrical work may be done by homeowners but I am not clear on the limits of that. I would expect that it does not extend to 3-phase wiring. I would expect for this that the township or or municipality requires signed and sealed design drawings from an engineer (the electrician should know though)..

I will leave this open for now but with a short leash and I will bring it up for discussion in the moderators forum.
 
Last edited:
doggy said:
We are getting 3 phase power delivered to our property via our own dedicated transformer. We want to rewire the house and other buildings so that we can use different appliances on different phases. We have 4 air conditioners, 3 hot water units and the usual assortment of things you would find in a house. The other buildings have a similar setup.

It seems to make sense to split the hot water units across each phase and to do something similar with the air conditioners.

But the big question is what sort of distribution unit do I need to achieve this? It will have 3 phase power going in and then it needs to supply single phase circuit breakers that may each be connected to one of the three phases.

We also want the system to be protected by an RCD.

Is this doable?
So it sounds like you have had your local power utility route power to a pole at the edge of your property, and are asking how to proceed from there. It is of course do-able to now bring that power onto your property and use it in the best way, but asking for advice on a web forum about how to engineer and install such a system is the wrong way to go about it. Instead, hire a licensed engineer and electrician to design the system, pull the permits, install the system, and get it inspected and signed off.

If there are any mistakes made in the design and implementation of the system, you could be liable for any injuries or damages caused (both on your property and off your property if you start a fire that spreads to other properties).

DaveE said:
Yes, it's probably doable. But it does depend on the details.

Your next, AND ONLY GOOD CHOICE, is to hire an electrician. This falls into the category: if you have to ask the question, you don't have the knowledge to do it yourself.
This.

Thread will remain closed.