Fusing down for a cloakroom fan with timer
- Thread starter DIYedboy
- Start date
Sponsored Links
Neither actually requires it - but some manufacturers call for fusing for their product so, yes both -
or buy one where the manufacturer does not call for it.
or buy one where the manufacturer does not call for it.
If you do insist on fusing down to 3A,
assuming this is a timer fan activated by the light,
you can fit one fused spur at 3A serving the whole room, ie the light as well.
This way you only need one fuse which will protect both lives.
Having two fuses for each live wire seems naff.
assuming this is a timer fan activated by the light,
you can fit one fused spur at 3A serving the whole room, ie the light as well.
This way you only need one fuse which will protect both lives.
Having two fuses for each live wire seems naff.
In the real world: No.
In the fantasy world of fan manufacturer instructions: Yes.
Sponsored Links
- Joined
- 27 Jan 2008
- Messages
- 23,728
- Reaction score
- 2,675
- Location
- Llanfair Caereinion, Nr Welshpool
- Country
In the main bathroom extractor fans have very thin wire in the winding and to protect the fan from burning out due to being stalled would need a fuse in the milliamp range. So in real terms the fuse only really protects the wiring, so be it 6A or 3A is really no difference the motor will still burn out first.
Clearly all cable needs some current limiting device, so one would not connect to the 32A ring final without some thing to reduce the current before the circuit opens.
As to the permanent line and switched line it is likely that the switched line is simply a trigger, but manufacturers don't tend to tell you if that is the case or not, so both have to be treated the same.
The big question is if the fan is required under building regulations or simply that the air needs changing? The building regulations talk about natural light and ability to open windows and often a simple trigger when the light is turned on is not enough, double pole switches, pneumatic timed switches, and PIR's may be required to comply with building regulations, but if fan is not required then a simple light trigger is enough.
However having a fuse has a second use, should the fan become faulty then you want to be able to isolate fan so light still works, in this house the fan isolator is always turned off, fan was fitted to get completion certificate and once issued never used again.
Clearly all cable needs some current limiting device, so one would not connect to the 32A ring final without some thing to reduce the current before the circuit opens.
As to the permanent line and switched line it is likely that the switched line is simply a trigger, but manufacturers don't tend to tell you if that is the case or not, so both have to be treated the same.
The big question is if the fan is required under building regulations or simply that the air needs changing? The building regulations talk about natural light and ability to open windows and often a simple trigger when the light is turned on is not enough, double pole switches, pneumatic timed switches, and PIR's may be required to comply with building regulations, but if fan is not required then a simple light trigger is enough.
However having a fuse has a second use, should the fan become faulty then you want to be able to isolate fan so light still works, in this house the fan isolator is always turned off, fan was fitted to get completion certificate and once issued never used again.
I would personally say 'potentially dangerous' rather than just 'naff' - since someone might think that they have rendered the fan 'safe to work on' by isolating it by switching it off (and maybe also removing fuse) at one FCU, not realising that there was a second one which also needed to be switched off.
However, as has been said, the electrical argument for fusing down from 6A to 3A at all is extremely weak.
Kind Regards, John
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
Sponsored Links
