3 Pole Fan Isolator C/w Fuse.

[Evans Electric]

As an extension to a recent thread by a DIYer  I think this is worth throwing out for comment .

To answer the call to seperately fuse timer fans various makers have produced a 3 pole switch c/w a fuse .

I have not seen or used them as yet  but would state that confusion may reign . 

I would suggest that the lighting feed for that room MUST be routed via the fuse ,  the light & fan would be dead if fuse blows.

Light & fan should be treated as a single unit  ....for isolation purposes.

Any other configuration could be dangerous .

I've lost count of the number of DP switched spurs which switch L &N  to the fan but leave the SL live  ( if light is on) 

Any comments would be welcome .

 

[NozSpark]

I would suggest that you maybe possibly correct

I have never seen a switch fuse supply only the line and neutral of an extractor fan with the sw line not being protected by it

 

[Evans Electric]

Yes loads of them TBH    .  They'd be better switching the L & SL  and linking the N through TBH

 

[Andy™]

but then the neon wont work

 

[ProDave]

Like others, not seen one yet. I'll get one on my next order.

The only way I can see them working, is for the fuse to be completely independent to the 3 pole switch, so you can use the fuse to feed the supply to the light switch and hence fuse the light as well.  Any other configuration will only fuse the permanent L or switched L, not both.

Personally I don't get wound up with the need to fuse the feed to a fan, but that's just me. 

 

[NozSpark]

TBH I think they are a great idea,,, I often loop at a fan isolator so they'd work quite well for me

 

[steptoe]

Ive used them a couple of times when spec'd,

wire light as normal [except sw], then 3c to fan isolator, and 2c from isolator to sw, 3c from isolator to fan.

 

[Evans Electric]

I forget a lot of the crap  stuff thats thrown at us lately  TBH (  I have other concerns and view most of these committee based revolutionary alterations to the Regs or wonderous new ways to notify jobs  etc  with a very jaundiced eye these  days )  .........but I do remember reading  recomendations for fusing timed fans and not relying on the lighting MCB for protection . 

 

[Evans Electric]

Ive used them a couple of times when spec'd,

wire light as normal [except sw], then 3c to fan isolator, and 2c from isolator to sw, 3c from isolator to fan.

That makes sense  Stepps  & keeps it simple.

 

[steptoe]

That makes sense  Stepps  & keeps it simple.

thats me Deke,

simple,

why overcomplicate and make work where its not needed.

 

[Evans Electric]

Same here Stepps ,  quickest way from A & B is a straight line .

 

[Murdoch]

Keep it simple.

As long as its on a 6A MCB, Greenwood fans DON'T require fusing down!

 

[Steve3948]

Its not only Greenwood, some Vent Axia and others say from lighting circuit or fused at 3A.

Many previous threads on this if you do a search.

 

[binky]

anyone ever known a fan to 'melt' ie need a 3A fuse - have to say it's probably the only bit of electrical kit I've never seen burn't out!

 

[Steve3948]

anyone ever known a fan to 'melt' ie need a 3A fuse - have to say it's probably the only bit of electrical kit I've never seen burn't out!

And with a 3A fuse it still would have.

 

[Evans Electric]

Have to agree with the last few posts ....OTT with the 3A fuse really...

 

[ProDave]

Does anyone actually read the instructions with a particular fan? I rarely do. As long as the terminals are clearly marked, there's no need to.

you will be telling me you read the instructions that come with a light switch next.