Question

(ii) A second drill is used with the extension lead. The power of this drill is

1200 W.
The instructions for using the extension lead include the following information.
When in use the lead may get hot:
DO NOT go over the maximum power
lead wound inside the case: 820 watts
lead fully unwound outside the case: 3100 watts
It would not be safe to use this drill with the extension lead if the lead was left wound
inside the plastic case.
Explain why

Answer 1

Answer would be No. it would not be safe to use this drill if the lead/cord was left coiled up inside the recoiling extension cord.


Maximum wattage of the lead is derated down to 820 watts max. Due to heat build up without cord open to free air cooling.

1200 watt load needs the unwound rating of 3100 watts to be truly safe.