Fuse rating...

[Koldov]

Can any DIY (or qualified) electricians tell me why nothing seems to come with a specified fuse rating these days?

 

I recently moved house and sadly left my Nuaire PIV, but upgraded to heated Vent-Axia version in the new house.

 

Unfortunately I had a few problems with the first one I purchased and the second also seems to have a few little quirks...

 

I found that some of the issues I was experiencing, seemed to stem from the fact that I appear to have an older firmware as some of the menu items in the included (and on the website) instructions were just plain wrong. Things like the instruction manual (and the sticker on the unit) plainly stating the fan speed as adjustable between 19-49L/s but my unit having the options of setting 10-60L/s...

 

However, trawling through the internet, I discovered an older version of the instructions that actually seemed to line up with the menu items and settings on my unit and this is where I found the switched spur was originally described as fused (3A).

 

NEW

 

 

OLD

 

 

I had emailed support explaining the issues (I also asked why there was no fuse rating specified for the fixed wiring switched spur and was the unit itself fused internally) and received this reply:

 

There is no requirement for the product itself to be fused as this is a requirement of the installation for the electrician to make sure it meets current IEE regs. This is why the comment has been removed from the manual.

 

Does this mean it is now incumbent upon the electrician installing a device to work out the draw and appropriate fuse rating? Although I still can't see the reasoning behind removing the instruction that the unit should be on a 'switched fused spur', even if they no longer need to advise of the rating required...?

 

I've also been looking at security lighting and notice none of the products specify what fuse rating it requires, although this might be different, it can't be assumed it will be wired into the house 5A lighting circuit as advice varies such as "Security lights can be wired into an existing lighting or power circuit, or to an exterior outlet with a transformer. You can also hardwire the lights to a switch." ...so why not include the required fuse rating?

[PotNoodleTech]

I think what they are saying is it is an installation issue and thus up to the installer (electrician) to make sure it is safe the correct wiring thickness correct fuse on the spur and ultimately correct MCB rating.

 

If the electrician wires up far too many computers onto one 32 amp breaker, that is the electricians fault not the computer manufacturers fault and they Dell won't reccomend the breaker size as it's purely an installation issue not a manufacturer issue.

 

See what I mean?

[speakercon]

Most bathrooms fans would be powered from the 5A/6A lighting circuit through one of those bathroom fan isolator switches which are not fused. So technically not adding a FCU would have been against the manufacturer instructions so maybe they removed it for that reason, as adding one would add unnecessary work/expense.

 

Probably the same with the lights, no need to add a FCU if on a lighting circuit.

[Koldov]

I think what they are saying is it is an installation issue and thus up to the installer (electrician) to make sure it is safe the correct wiring thickness correct fuse on the spur and ultimately correct MCB rating.

 

If the electrician wires up far too many computers onto one 32 amp breaker, that is the electricians fault not the computer manufacturers fault and they Dell won't reccomend the breaker size as it's purely an installation issue not a manufacturer issue.

 

See what I mean?

 

Yeah, I do but... I think I'm getting at the equivalent of plugging in the units themselves to the wall sockets, not the breaker/consumer unit behind them. Taking your example, I guess I'm talking more about the IEC leads that come (fused) with the product. In that instance it would be like shipping the computers with no leads and no information on what fuse to put in to the lead you'd have to supply...?

 

Most bathrooms fans would be powered from the 5A/6A lighting circuit through one of those bathroom fan isolator switches which are not fused. So technically not adding a FCU would have been against the manufacturer instructions so maybe they removed it for that reason, as adding one would add unnecessary work/expense.

 

Probably the same with the lights, no need to add a FCU if on a lighting circuit.

 

True, although I had an expensive SELV Envirovent bathroom extractor fan in the last house (which I also left)... they even go a step further and include the switched fused spur and it had to be used even when coming off the lighting circuit!

 

 

As for the lights, yes no need to put an extra fuse in the line when coming off the lighting circuit, but I've seen a lot of installations that come off sockets, so just wondered why no fuse information is included (as you'd have to fuse it coming off a socket).

 

EDIT: Also the PIV has a 500W heater, so not just a 'bathroom fan'.

Edited December 16, 2024 by Koldov