Trouble designing a 3 phase wire heating element for DIY heat treatment furnace

Thread Starter

davemorl

Joined Jun 14, 2018
20
Hi all! I am looking for a bit guidance for sources of reading on designing a heating element in a delta configuration to output around 12kw of heating for 400v 3 phase. I would be looking to calculate wire diameter and length for each leg and also surface load on the heating element.

I would be looking at using a PID controller with a 3 phase solid state relay with a thermocouple and kanthal A1 wire.

There is loads of info for single phase but I'm struggling to find much on 3 phase.

Dave
 

Hymie

Joined Mar 30, 2018
1,282
It should be a fairly simple matter to modify calculations based on the use of a single phase supply with 230V across one heating element to three phase (delta) with 400V across each heating element – with each element rated at 4kW (to give a total load of 12kW).
 

Thread Starter

davemorl

Joined Jun 14, 2018
20
If it is as simple as that then I should manage no problem.

I thought it would be more complicated for some reason. Just connecting each end of the heating elements from each 4kw leg then from each phase?
 

Hymie

Joined Mar 30, 2018
1,282
Yes, the voltage between phases is 400V where the single phase supply (to neutral) is 230V.
So each heating element (connected in delta) will have 400V across it.
 
Top