A ground fault circuit interrupter (or Residual Current Device, RCD) must not be installed into the heater’s electrical circuit, as the heater is sufficiently protected when earthed. Fault current protectors are designed to ensure the safety of small electrical appliances, such as a coffee maker.
According standard 60364-7-703 (Electrical installations of buildings) part 703.412.5, the sauna heater shall not be connected via residual current protective device (RCDs). Only a certified electrician is allowed to connect your electrical sauna heater.
703.412.5 Additional protection by residual current protective devices (RCDs)
Additional protection shall be provided for all circuits of the sauna, except for the sauna heater, by the use of one or more residual current protective devices with a rated residual operating current not exceeding 30 mA.
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