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. This is simply a rotary on/off switch but should be sited more than 2 metres away from the hot tub so that bathers cannot be in the hot tub whilst touching the switch.
The electrician should fit a suitable weather proof block connector to the end of the tail from the isolator, the hot tub supply can then be directly hard wired into the weatherproof block connector inside the hot tub. Waterproof gland packs should be used to prevent ingress of water on all electrical connections (2 at the isolation switch). Ensure that all earth cables are clearly colour coded with green/yellow insulating tape or earth sleeve.
The electrical installation must comply with BS:7671 – “Requirements for electrical Installations IET Wiring Regulations”, particularly concerning the following specifications:
The hot tub must be hard wired on its own fused spur back to your household consumer unit, not sharing a supply with any other appliances
The hot tub should be protected by a sufficiently rated MCB (mains circuit breaker) and should cover the maximum amperage pull of the Spa plus 25% to allow for brake torque (i.e. the extra rush of current when pumps are first started). Therefore, a hot tub that has a maximum current draw of 20 amps should be fitted with a 25AMP MCB.
The hot tub should be protected against earth faults by an RCD (Residual Current Device). This is a trip switch which prevents the possibility of an electric shock from damaged or waterlogged cables and connections. A suitable rated 30mA RCD is recommended.
Outdoor cabling should be protected from damage by either laying protective ducting (pc pipe) below ground or by using Steel Wired Armoured (SWA) cable. Your electrician will calculate the size of cable required depending on the loading and the distance from the mains supply.
Once the hot tub is filled with water and the electrical supply is installed our installation team will commission the hot tub and check that everything is fully operational before handing over to you with a complete chemical training guide and hot tub features.
If you are in any doubt about the required electrical guidelines you should seek professional advice from a fully qualified electrician.
Please note: It is advised that your electrician leaves enough spare cable attached to the isolator to go the furthest side of the hot tub, usually a minimum of around 7m to 8m is recommended. If your isolator is located further away, then please use a longer length of cable.Our technicians are qualified to connect this cable to the inside of the Hot Tub.