3 phase pottery kiln

[kilnman]

Help please. We have had a three phase pottery kiln (16.08Kw and 22.8 Amps)that has just been connected but would like to double check that the three phase armoured cable is sufficient to handle the load. The 32 meter long cable runs through a roof void resting on mineral wool insulation. The four cables in the armoured cable are 6mm ( we had been told that 10mm would be used). The secondary meter board has a three phase trip rated at 32 Amps and the cable passes though a RCD before the secondary meterboard.
This new cable replaces one that was much thicker which is why we would appreciate a second opinion. Many thanks.:bow:

 

[telectrix]

if your load is 22A per phase and the breaker is 32A, that's fine. 6mm is rated at 47A when not enclosed in insulation. a 32A MCB is ideal for the cable and the load.

 

[kilnman]

Thanks for your reply Telectrix. I forgot to mention that the lenth of the armoured cable is about 32 meters long. does this make any great difference?

 

[telectrix]

could do on volt drop. hang on i'll do a quick calc. volt drop will be about 5.75v, so well under the limit. :stooge_curly:

 

[kilnman]

Thanks Telectrix for you speedy answers. Your knowledge is much appreciated. All the best.