Garden Sauna - Earthing arrangement (loss of PEN conductor)

[GazB]

Hi Guys,
Got a question, I'm relatively new to the game so bear with me. I've got a situation where there's an outside sauna to be fitted and the house earthing arrangement is a TN-C-S (PME), I was wondering whether or not the Sauna would need to have a TT earthing arrangement or a PEN monitoring device similar to an EV charger or not? I'm unsure on this and struggling to find in the BS7671, although your outside you are inside of the Sauna.
Id appreciate any comments, thanks in advance.
G

 

[binky]

Exporting the earth outside of the equipotential zone is considered bad practice. Rod it.

 

[Sidewinder]

TT the sauna supply.
Make sure that no touch voltages are within reach of the sauna, that is, nothing conducive and connected to the TN-C-S earthing system can be reached from the sauna.
A broken PEN device is ONLY suitable for use in conjunction with EVSE.
Personally, I don’t think that these broken PEN devices are suitable for anything. I don't trust that they are actually safe.

 

[Gian]

TT the sauna supply.
Make sure that no touch voltages are within reach of the sauna, that is, nothing conducive and connected to the TN-C-S earthing system can be reached from the sauna.
A broken PEN device is ONLY suitable for use in conjunction with EVSE.
Personally, I don’t think that these broken PEN devices are suitable for anything. I don't trust that they are actually safe.

May I ask in more detail why you don't think they are safe.are you talking about stand alone and ev chargers with them built in.have you had some bad experience with these units

 

[Sidewinder]

I have not yet seen compliant documentation for one.
I have not seen one that states that the electronics and software complies with recognised international standards.
The devices are explicitly for EV charging, nothing else.
They are not designed with the parameters for protection of people related to their use in conjunction with hot tubs and similar, ONLY EV charging.