openinverter forum

Not EV specific but thought someone here would know.

I have 3phase in my workshop. The outlets have 3 phases and an earth but no neutral. This is 4 pin.

I have an appliance that has a 3 phase plug with 3 phases plus a neutral and an earth. This is 5 pin.

Can the appliance be adapted to the outlet or rewired? Or are the 2 setups totally different and incompatible?

The appliance is a commercial oven. It has a single phase motor for the fan. And 3 heating elements which have 1 phase each plus a the common neutral.

I think it could be rewired to run single phase with 1 element, but might be too high amp draw from a domestic wall socket (15 amp) and would be good to use the 3phase I have.

I got the large oven for powder coating. Any thoughts?

Are the heater elements wired in star? If so, they form a virtual Neutral at their star point. If the fan motor load is relatively small, then just power it from one phase, plus the star point.

Do you have 240V single phase in the workshop too? If so, you have a Neural at your distribution panel that could be pulled through.

1 of the 3phase outlets in my workshop has a neutral. Currently it is hardwired to the mill. I just need to put a 3 phase plug on the power lead to the mill and replace the wall switch with a socket outlet. Then I can have the mill and oven share.

If the appliance needs a neutral then you need a neutral. Should be available in your distribution board. Maybe tucked up inside the outlet housing.

xp677 wrote: ↑Sun Mar 01, 2020 11:00 pm If the appliance needs a neutral then you need a neutral. Should be available in your distribution board. Maybe tucked up inside the outlet housing.

Neutral is definitely available at the distribution board. The distance to the board and the number of finished walls to go through is the issue

I think I have a another solution. But confirmation that an appliance wired for neutral cannot be rewired is helpful to know. Thanks.

I recommend reading up on three how three phase power works. Search for "star" vs "delta" wiring. It should become clear quite quickly why you need to match them.

I have had this issue before, a welding shop which was being converted into a machine shop. All the outlets wired for 4 pin, no neutral. Had to run all new neutrals from the board. Laziness and cost cutting during original install. It's easy to go from 5 to 4 pin, not so much the other way.