He would need 2.5 sq. mm. Cu flex wire for heater wiring........... 3 runs if heater is Delta connected, 4 runs if heater has a star connection which includes provision for neutral wire. Obviously earthing wire has to be considered seperately.
Hope this helps.
Wire size is based on current drawn by the load, not on voltage or phase or application. 2200KW divided by 415V is 5.3KA. Wire will need to be 2015 sqmm or larger. Are you sure the 2200KW figure is correct?
Yeah I'm not sure about this one ...... I like the look of b.shahvir idea of 2.5 a lot better.
Thanks for the suggestions, they have helped.
EDIT
Come to think of it .... he did say it was 2200KW, that is a silly figure. I know the bloke likes to keep warm but there might be a mistake in here somewhere.... and he said he wanted to run 2 of them !