Using extra low voltage with a volt free thermostat, re-IET regulations.

[ericmark]

One channel only: Note that the output contacts are voltage-free*

* Not SELV - Fixed wiring only, to comply with current IET regulations.

Not surprised, but what IET regulation? Quotes from Drayton Wiser installation instructions. I have said that the three options are

asking for problems, where the wrong thermostat is used on the backplate, which is so easy to do. The "Link for 230V output" seems to suggest one can use another output voltage, and we have FELV and PELV as well as SELV, so why pick out just SELV?

 

[CountryFan]

Not sure Functional or Protected apply in this situation?

 

[ericmark]

The document it seems written in 2023, I do not have BS7671:2018 so don't know what the IET regulation is what stops the single channel being used with SELV controls using the backplate. Since it also has the option to use OpenTherm.

I have read on this forum the module is included with the kits 2 and 3, and it does work, what I would be interested in is if other hubs, thermostats, or programmers using the same backplate has the same warning.