Information required about fused switch-boxes and alternatives to these.

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I am hoping that someone will be able to advise me about a technical/purchasing problem.

In our bathroom is a ceiling rose (this is in addition to the light in the centre of the ceiling), from which a flex emerges. This flex (it is thick enough to carry a full 13 amps) is connected to the mains supply in the loft. It was installed, years ago, by me. In my ignorance, I did not put any kind of fuse between this mains outlet flex, and the bathroom extractor fan. I have since realised that the fan ought to be protected by a 3-amp fuse, of course, but I am in a quandary as to how to find a fused switch-box of a kind that will allow me to address this problem. If I were to use a standard fused switch-box, it would be necessary to chisel the plaster, down from the ceiling to the switch-box (so as to bury the flex in the plaster), but I am very reluctant to spoil the decor of the bathroom. And anyway, the flex (ultimately, connected to a junction box in the loft) might not be long enough to allow this, as it droops down from the ceiling rose and, traversing the distance at an angle, goes into the top of the fan casing (i.e. I don't think it could accommodate a right-angle). I am no longer able to go into the loft, and replace any existing flex, or spur-cable, with a cable long enough to accommodate the right-angle that would be required. Besides, there is so much stored junk in the loft, that to look for the junction box would be a nightmarish task.

It’s relevant to point out that our consumer unit has very sensitive flip-switch circuit-breakers, and not the old-type fuses.

What I am hoping is that, somewhere, a fused switch-box may be found that has a grommeted entry-hole at the top of the casing (instead of the mains cable entering the box at the rear). This would then allow me simply to screw the switch-box to the wall, lead the mains-flex into the box, and let it emerge from the bottom of the box (with a fused switch in between the two), thus making the fan 100% safe.


My question is, therefore: are such a fused, top-entry switch-boxes made, and can anyone tell me where one to buy one?


Failing that, is there such a thing as an in-line fuse (3amp) that might be inserted into the existing flex, and not look too incongruous?
 
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Is your fan connected to the lighting circuit ,when you say mains supply ? Or do you mean it's connected to a power ( socket ) circuit ? If the former ,is the circuit for lights protected by a 6 amp MCB ? If so why do you think you need a three amp fuse ?
 
Is your fan connected to the lighting circuit ,when you say mains supply ? Or do you mean it's connected to a power ( socket ) circuit ? If the former ,is the circuit for lights protected by a 6 amp MCB ? If so why do you think you need a three amp fuse ?
Terry: When I say the mains, I mean the power supply, not the lighting circuit. As I said in my OP, it is connected into a junction box in the loft (so really, it's a spur from the ring main circuit).
A.W.
 
OK ,so is your plan is to mount a surface mounted box ,for the fused connection unit .if so the box has knock out sections to accommodate cable entry from all sides ,as well as from the rear.Does that fit the bill ? It would be better if you wired the fan into the lighting circuit ,but I understand the loft clutter may put you off.
 
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. Is your plan is to mount a surface mounted box ,for the fused cu .if so the box has knock out sections to accommodate cable entry from all sides ,as well as from the rear.Does that fit the bill ? It would be better if you wired the fan into the lighting circuit ,but I understand the loft clutter may put you off.

I would greatly prefer a (plastic) fused switch-box with a cable entry from the top, but even if it had to be a side-entry, it would do. Yes, the clutter in the loft is too much to bear thinking about moving (at 85, I'm past that). I am taking the kitchen fan as my guide, where the fuse is concerned. That works with a 3-amp fuse. The one in the bathroom (the subject of this discussion) is more powerful, but I think a 3-amp fuse would be enough. In any case, when I have the time, I may be able to find the leaflet that came with this fan — perhaps.
A.W.
 
They allow cable entry from top / bottom/ sides and rear. You just carefully remove the bit that you need to.
 
top-entry holes need to be more thoroughly sealed, as dirt and other matter is more likely to fall in.

plastic CUs are no longer installed as it is not fireproof.
 
I think I've understood your problem.This little beastie appears to have 20mm knockouts top and bottom (other suppliers are available and probably cheaper) so add a couple of these https://www.screwfix.com/p/tower-male-comp-gland-white-20mm-pack-of-2/45943 and you should be chuckling with one of these fitted into the box https://www.screwfix.com/p/13a-switched-fused-connection-unit-spur-white/2323d (again other suppliers are available, though annoyingly B & Q no longer offer 10% discount to pensioners on Wednesdays :(.
 
You do not need a "fusebox" (consumer unit.
Even if it is connected to a socket circuit fused at 32A, you only need an FCU
 
They allow cable entry from top / bottom/ sides and rear. You just carefully remove the bit that you need to.

Terry, what are these things called? If I don't know that, I cannot buy one. Can you tell me where to look for one?
A.W.
 
I think I've understood your problem.This little beastie appears to have 20mm knockouts top and bottom (other suppliers are available and probably cheaper) so add a couple of these https://www.screwfix.com/p/tower-male-comp-gland-white-20mm-pack-of-2/45943 and you should be chuckling with one of these fitted into the box https://www.screwfix.com/p/13a-switched-fused-connection-unit-spur-white/2323d (again other suppliers are available, though annoyingly B & Q no longer offer 10% discount to pensioners on Wednesdays

Hi, friend. These glands are nothing to do with my problem. I thought I had explained clearly. Also, though you mean well with the fused switch-link, that won't do either. It would surely require a metal box, and wall chiselling to fit it.
A.W.
 
One gang surface pattress box ,white. Different depths available ,32 mm would be around what you need ,deeper if you like. More depth means more space for connecting /cables ,but look less neat.
 
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Hi, friend. These glands are nothing to do with my problem. I thought I had explained clearly. Also, though you mean well with the fused switch-link, that won't do either. It would surely require a metal box, and wall chiselling to fit it.
A.W.
Now I'm confused. I understood you wanted a backbox you could screw to the wall, feed the flex in at the top & out at the bottom and onwards to the fan. You don't have to have a metal backbox set in the wall, a plastic surface box is perfectly acceptable. The glands are to provide strain relief to the flex ( you wouldn't usually use them with installation cable since the cables are held in place by clips or plaster)- you remove the knockouts top and bottom of the backbox, insert the gland and then thread the cable through the gland.
In all this, we've all ignored the fact that you're in a bathroom so zones apply- your new FCU would have to be at least 600mm from the bath/shower OR more than 2250 above floor level
 
One gang surface pattress box ,white. Different depths available ,32 mm would be around what you need ,deeper if you like. More depth means more space for connecting /cables ,but look less neat.

Terry, thanks for that. I take note, also, about the varying depths.
A.W.
 

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