07: 703 Rooms and Cabins Containing Sauna Heaters (254)

Question 1

Only the sauna heater and equipment belonging to the sauna heater shall be installed in (703.512.2 p.254 and Figure 703, p.255)

a) Zone 2
b) Zone A
c) Zone 1
d) Zone B

Answer 1

c) Zone 1

703.512.2 p.254-255
External influences: The equipment shall have a degree of protection of at least IPX4

Where cleaning by use of water jets may be reasonably expected, electrical equipment shall have a degree of protection of at least IPX5.

Three zones are defined as shown in Figure 703:
i) In zone 1: only the sauna heater and equipment belonging to the sauna heater shall be installed

(ii) In zone 2: there is no special requirement concerning heat-resistance of equipment

(iii) In zone 3: the equipment shall withstand a minimum temperature of 125°C and the insulation and sheaths
of cables shall withstand a minimum temperature of 170 °C (see also Regulation 703.52 for wiring).

703.52 p.255
Selection and erection of equipment: Wiring systems:
The wiring system should be preferably installed outside the zones, i.e. on the cold side of the thermal insulation. Where the wiring system is installed on the warm side of the thermal insulation in zones 1 or 3, it shall be heat-resisting. Metallic sheaths and metallic conduits shall not be accessible in normal use