Article: In some cases, unless the circuit has been installed by a licensed contractor and then approved by a local building/electrical inspector, the manufacturer won't recognize the warranty. The power that runs the hot tub must be given a dedicated circuit because of its electrical demands. No other appliances or electrical demands should share the power. Again, if there is any doubt about how to wire the circuit responsible for the hot tub, use a licensed electrician. Otherwise, here is some important information about wiring that you should know:  The size of the wire you use must be approved by the National Electrical Code (NEC) and/or local codes. The size of the wire you use should be based on the length of run from the breaker box to the hot tub. The maximum current draw should also play a role in determining wire size. Copper wire is recommended with THHN (thermoplastic nylon) insulation. In fact, all wiring should be copper; aluminum wire should be avoided. If using wire larger than #6 (10mm2), be sure to put a junction box close the hot tub. Then, reduce the wire to short lengths of #6 (10mm2) in between the junction box and the hot tub. When it comes down to it, saving a few hundred extra bucks isn't worth the potential disaster of voiding the warranty or causing serious bodily harm or death. Please see a professional if you no experience wiring electrical circuits.

What is a summary?
Know that some warranties will be voided if the electrical circuit isn't installed by an electrical contractor. If you decide to do the wiring yourself, keep the power on a single dedicated circuit. If wiring on your own, make sure your specs are right. If you have any doubts, use the services of a professional.