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Posted By Topic: 2 phase balancing

Mar 11 2020 08:03

Hey guys

On my first two phase house, been given a way to balance the phases but I just want to get your guys advice on the best way or the way you guys balance the phases out


Mar 11 2020 10:34

Assuming you'll have RCBO's or RCCB's protecting two power and one lighting circuits each, split them over the two phases 50:50 (or as close to that as possible).

Them the remaining circuits (HW, oven, hob, AC) also split between the two phases. Not much more to it then that.

You could use the maximum demand tables in AS/NZS 3000 alternatively.

Mar 11 2020 20:29

Quite often depending on the installation and situation a hob, oven, one light circuit, and one power circuit can be put on one phase and the rest on the other but it really depends on the individual domestic situation.

Also keep note on which phase the hot water cylinder is actually fed from as this adds a considerable amount on demand

Mar 12 2020 07:08

Is this a big house or could it be downgrade to 1 phase and save the owner on line charges
Be careful often older house had two phase and 1 is used for off peak heating or other larger controlled loads.
If you put the wrong stuff on the off peak retailers get mighty upset at the consumer getting cheaper power on normal use.

Mar 12 2020 09:02

Shouldn't be possible to connect uncontrolled loads to a "controlled" meter without breaking seals.
And if the new 'whatever' only operates at off-peak times, the retailer has nothing to complain about.