I can't make sense of this chart. For the column "Drop 9" with 9kw output, what kind of amperage does the heater draw?


Here's another diagram if that helps. enter image description here

1 Answer 1


Your device has 3 heater elements - so for the 9kW version, each element produces 3kW of heat.

Your drawing indicates that each element is fed with a 230V supply - so 3kW from 230V requires 13A each.

Now if you refer to the "Circuit breaker" column you'll see that your 9kW device can be supplied by a 3-phase supply with 3 x 16A breakers, or if you connect all 3 elements together to the same single-phase breaker then it must be 50A.

The "Power cable" column appears to be telling you what size cables you need, and the numbers given include the Neutral and Earth/Ground wires.
So if you feed your 9kW device from a 3-phase supply, you need 5-wire cable, each wire 2.5mm2, or for a single-phase supply you need 3-wire cable, each wire 10mm2.


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