How is the connection for a 3 phase 4 KW commercial kitchen hot plate?

Question

I am confused with 9 pole selector switches and 4 terminals on the 2 phase heating plate.

Answer 1

look for the manual or call the manufacturer...

Answer 2

1. At 4KW. I doubt if it's a three phase unit.
I would expect two phase and one neutral connection
for a unit that size.
2.The connections should be marked at a source
junction box. the installer should not be working
inside the switching modules in the unit.
3. You should probably have or provide an external disconnect.