3-Phase Multiple Questions NZ

patisseriekf · Mar 28, 2021

Hi,

I am a pastry chef in New Zealand and am wanting to build a kitchen at my home. Either convert the garage or preferably build it on a food trailer. It will be set in one place as I will not be selling directly from home. Just catering out. But if on a trailer I can move it easily at a later date.

I am really struggling to understand 3-Phase power here.

The oven I want to purchase are big deck ovens that run on 3-phase as well as a pastry sheeter and some other equipment that all seems to run on 3-phase too.

There is no 3-phase to the property I am in. I hear it is incredibly expensive to get it installed but can't find where to get this information.

I also see some talk of converting appliances to run on single phase or using an inverter?

I wouldn't have thought this was possible due to the power draw of the oven.

The oven I have my eye on has the following information:

3 P+N+E

400-415 V a.c.

50Hz

Power 28.4 Kw
L1 40 A
L2 44 A
L3 38 A

I have no idea really what any of this means and advice on my options going forward would be much appreciated.

Cheers

James · Mar 29, 2021

The power requirement for 1 oven is around 125Amps if it were single phase.
realistically, there are not many options.

enquire with your energy supplier about the cost of a 3 phase supply
buy a much smaller oven
hire or buy a 3 phase generator

if you go down the route of generating , bear in mind the generator will be near the size of a small car and use around 3 litres of diesel per hour.

Vortigern · Mar 29, 2021

Last time I checked, here in England, it costs circa £100k to set up a kitchen/restaurant. There is usually provision to wire up three phase equipment to a single phase by changing links at the point of connection. The oven you are speaking of seems to be unusually large amperage even for commercial. Are you sure you have it right, the amperage?

snowhead · Mar 29, 2021

I think you need to look as a simpler solution to start with for example renting space withinn a commercial unit or sharing with others in a similar position to yourself.

I will depend exactly where you live, in relation to the Electricity network as to whether you can have 3 phase and then at what cost.
NZ is similar to here in the U.K
There are 4 elements to the system,,

Electricity generating companies,
a National distribution company,
local network companies ( called Line Companies)
and finally energy providers.

It will be your energy provider who you pay you electricity bill to who you need to contact for a price to upgrade.
It may be that they pass you over to the Line company as they know what capacity is available in your exact location.
Also bear in mind that as a Commercial user you will probably have to pay a higher price for electricity useage and you may have issues using your house for commercial use.

I was in N.Z a couple of years ago and noticed that the Electricity network for older properties is fairly basic, with local transformers on the pavements and supplies to houses all overhead.
Newer properties seemed to be underground.
It would be cheaper to upgrade if your supply is overhead, but not if the local transformer does not have 3 phase available or is fully loaded.

DPG · Mar 29, 2021

Can't you use a gas oven?

ElectroChem · Mar 29, 2021

Talk to your electricity supplier. As @snowhead said, the best outcome will be if you have 3-phase overheads in your street and there is enough spare capacity to give you two more phases of say 63A each.

Also keep in mind, your kitchen/trailer will need to adhere to the requirements of AS/NZS 3000, 3001 and various other standards. Especially if you're planning to use it as part of a business. There is no DIY provision in AU/NZ regs, the inspectorate can and will shut you down if they find unlicensed wiring in your business.