For a 32AMP hot tub, 6mm² 3-core SWA cable is needed and a 10mm² 3-core SWA cable is perfectly suitable for a 40AMP Hot Tub. An IP65 45AMP Rotary Isolator Switch is also recommended so that the hot tub can be isolated outdoors in an emergency or for service work.

How much load can a 4mm cable take?

The standard load capacity of 4mm insulated aluminum wire is about 33A (at 30 degrees C), and 4 mm copper insulated wire is 42A. The bright wire can carry 7000W of electrical power, and the dark wire can generally bear the maximum electrical power at about 5500W.

How many amps can a 2.5 cable carry?

23-25 amps A 2.5mm cable is capable of supplying around 23-25 amps depending on the method of installation, so is fine, safe and compliant on a 20amp circuit breaker.