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[westhighland]

:? i want to fit a Double insulated Humidity Fan with Timer and a 6 amp fan isolator switch onto a lighting circuit protected by a 6 amp fuse but the fan instructions state that a double pole fused spur must be used and fitted with a 3 amp fuse. Can i proceed with this route, if not, then why not !


(You never stop learning)

[ericmark]

With two independent feeds the only way to fuse fan would be also to fuse the light as well. It is normal to use a triple pole switch for a fan isolator and these don’t tend to come with fuse as well. You don’t say where the fan is for? If for a bathroom then also it now required to be RCD protected. Using Screwfix No: 83049 Volex 13A RCD FCU feeding both lights and fan could kill two birds with one stone if not already RCD protected.
Even in a kitchen you may consider this as an option but screwfix No: 51728 Crabtree 6AX 3 Pole Fan Isolating Sw would have been normal method.
I am not saying use screwfix but using there numbers mean it is easy for you to find without me giving a link which we are not suppose to do on this site.
The instructions do seem a little strange as most lighting circuits as 6 amp and one would have expected a 6 amp rather than 3 amp limit and one does wonder how they intended you to use an all pole fused isolator with two feeds maybe the fan manufacture does an isolator special for their fan?
Eric

[westhighland]

Basically what they saying is connect the fan to a fused connection unit with a 3 amp fuse. The old, ceased working fan, not the same model as new was connected to this unit situated inside the bathroom. I would like to put the triple pole isolator switch outside the bathroom, the isolator switch is unfused, where it states 6A i assume this relates to the matching current, this would match the lighting circuit which is 6 amps and the consumer unit has a RCD fitted. The fan is a Domus H12 Humidstat model with adjustable humidity and timer controls and has N, SL, L connections, no earth required and i'm unsure as too how to connect it to the islator switch which has L1,L2,L3 x two.

[ericmark]

With a Humidstat there is no need to connect to lights in any way. And a normal two pole switched fused isolator is all that is required.
Eric

[westhighland]

:) The radial circuit was to supply the link to the what would have been the isolator but will now be a fused connection unit because it was more accessible than the ring circuit.