Is this right? Switch fuse spur

littlespark · Aug 26, 2021

Customer supplied shiny metal accessories, varilight through TLC.

the switch fused spurs are prebuilt from grid components, but where they have put the link, it shows line supply into fuse first, then through dp switch. Neutral only goes through switch.

I thought it would go through switch first, to isolate the fuse if you need to pop it out.

ive fitted them as is, as that’s how they’ve been supplied.

[ElectriciansForums.net] Is this right? Switch fuse spur

Come to think of it…. Shouldn’t it be a brown coloured link?

freddo · Aug 26, 2021

I fitted some of these recently, I moved the link so the fuse was dead with the switch off.

littlespark · Aug 26, 2021

There was 3 of these, all the same, so I just fitted them as is.
I know I could have moved the link, but that’s how they were supplied, and we shouldn’t tamper ?

Mikegh · Aug 26, 2021

At first glance it looks like the link is in the wrong terminals

Looks like it should go Lo on DP to Lin on fuse

freddo · Aug 26, 2021

I just don't like the idea of someone prying about with a screwdriver on something that is live in case the plastic breaks. Just look at the newer crabtree ones, some of the fuse holders require so much force to remove they either break or the carrier comes flying right out when it is finally freed.

Mikegh said:
At first glance it looks like the link is in the wrong terminals

Looks like it should go Lo on DP to Lin on fuse

That's what I did (with a new longer link).

Mikegh · Aug 26, 2021

Yes it appears to be a mistake

Wouldn't be the first time I've seen this sort of thing

As pointed out there's the question of should you move it or what to do , return it etc

Mikegh · Aug 26, 2021

As the term switch-fuse implies it's the norm to wire through the switch first afaik ?

For obvious reasons

littlespark · Aug 26, 2021

I just checked on the varilight website and for the model number XDS6DS the online instruction manual shows exactly how it is. Line goes through fuse first.

So I don’t think it’s a mistake in assembly.

timhoward · Aug 26, 2021

Interesting. As there's a UK phone number, and the instructions say to make connections according to relevant diagram, you could give them a call and point out the ****ing obvious.

I wonder if they are claiming anywhere that it complies with BS1363-4 and whether that in fact specifies the connection order!?

James · Aug 26, 2021

Switch before fuse is not a requirement, infact it could be fitted without the switch at all.

HappyHippyDad · Aug 26, 2021

I guess you wouldn't be isolating an unswitched fused spur before removing the fuse. The unswitched fused spur IS the isolator, and perfectly acceptable as such. However, if there was a choice, it does seem sensible to be removing a fuse which is not live.

westward10 · Aug 26, 2021

I wouldn't have thought it matters too much after all a standard unswitched fuse connection unit does not isolate the fuse carrier, as it is modular from separate parts it would not have to adhere to BS1363. I would ask them say it is being discussed on a worldwide forum and their reputation is on the line??

freddo · Aug 26, 2021

westward10 said:
I wouldn't have thought it matters too much after all a standard unswitched fuse connection unit does not isolate the fuse carrier, as it is modular from separate parts it would not have to adhere to BS1363.

Agreed, especially as you shouldn't be able to touch any live parts at any time, but it would be conventional that any switch fuse, from a small 13A one to one for thousands of amps, the switch would isolate the fuse. I have an old iron clad 13A switch fuse and even that switches the supply to the fuse.

None of this really matters at all as you can easily unplug a BC or ES lamp and touch the spicy metal parts in the lamp holder, few people care about that!

littlespark · Aug 26, 2021

Saying all this, the rest of the accessories were decent.
Taking out deta plain white, and the terminals were in the same order… so no having to twist the cables around to swap ‘em over…
Cooker switch was upside down to original, ie supply and load were top/bottom opposites, but at least they were on same side.
4 gang grid. top and bottom was ok but L/N were the other way round.

Simon47 · Aug 26, 2021

A few years ago I was helping a mate with his pad. He bought some fo those and I queried it with the manufacturer. It's a deliberate design decision so that the indicator on illuminated ones goes out if the fuse blows.
As others have said, people don't worry about un-switched units. But I wired them switch first anyway (his we non-illuminated).