Installation of wiring must be carried out observing the necessary fire safety standards and electrical safety measures. To select the correct wire cross-section, you must first calculate the approximate power of the entire network in a bath or sauna. Low power, about 1-2 kW, will have a network if it is supposed to use only lighting devices in the bath, but if a washing machine is also installed in the dressing room or they use a hairdryer, then the power of the network will be much greater, it will be necessary to add about 5 to the total power — 6 kW, so it will be much more reliable. And if the electrical wiring in the bath is incorrectly designed, then soon there may be a need to repair washing machines. If electro-intensive equipment is installed in the bath, then you need to add about 10 20 kW to the total power of the network..
In order to calculate at least an approximate power, you need to pay attention to the electrical appliance on which the numbers are written, and one of them indicates the voltage of the electrical appliance, and the second indicates its power in kilowatts. Usually, stoves designed for saunas have a low, medium power, so the voltage will be 220 or 380 V, that is, a three-phase or single-phase connection is required. It is better to leave the wiring work to special electricians who know their business well and will do the job correctly and without the slightest mistakes.