Hmm, something wrong here !

[SimonH2]

Fitting a couple of FCUs for a mate, got one out of the pack and immediately thought ... not quite right. How many people do you think would just follow the LOAD and SUPPLY markings ? Note the very generous earth terminal

Untitled

• SimonH2
• 8 Sep 2012
• 1

Back of Varilight FCU

 

[JohnW2]

Fitting a couple of FCUs for a mate, got one out of the pack and immediately thought ... not quite right. How many people do you think would just follow the LOAD and SUPPLY markings ?

Hmmm. Perhaps they reckon that the fuse is there to protect the switch

Kind Regards, John

 

[bernardgreen]

No harm in protecting the switch is there, it is double pole so a catastrophic fault could result in a short live to neutral. The fuse would be usefull then.

 

[SimonH2]

So we're all agreed that it's OK to have the fuse live (unswitched) when changing it then

 

[GaryMo]

There's nothing technically wrong with it as it's not like you can get your fingers on a properly shrouded fuseway and carrier. Unless the rubbish you're fitting doesn't match that description?
I'd like to point out if I'm using modules in a grid system then I'd automatically put the fuse after the switch as a preference.

 

[bernardgreen]

Good point, but then I seldom turned off the main switch when changing a wired fuse. So on second thoughts protecting fingers does support putting the fuse after the switch.

 

[GaryMo]

And another point - what about unswitched fused spurs?

 

[Adam_151]

Good point, but then I seldom turned off the main switch when changing a wired fuse. So on second thoughts protecting fingers does support putting the fuse after the switch.

The instruction to turn off the board when inserting a fuse is not only due to the risk of touching the fuse carrier pins (which you seem to be aware off) but also the risk of replacing a fuse when there is still a fault in place (of which you make no mention) which is likely to result in damage to the fuseway and carrier not to mention bits of failed fuse wire not being properly contained.

 

[JohnW2]

Hmmm. Perhaps they reckon that the fuse is there to protect the switch

Several of the subsequent posts seem to imply that some people believe that the manufacturer deliberately and correctly intended it to be as it is - which hadn't actually occurred to me as a possibility when I made my initial jovial response. Is that what some of you believe? Simon, was there perchance a wiring diagram that came with it? (or, at least, what manufacturer are we talking about?).

Kind Regards, John

 

[SimonH2]

Simon, was there perchance a wiring diagram that came with it?

Yeah, probably - but on the basis that when you've seen one instruction sheet for fitting a socket you've seem 'em all, I didn't actually look at it

(or, at least, what manufacturer are we talking about?).

They're varilight screwless brass fittings. The FCUs were no problem, but the socket was a flippin nightmare - seemed to be no clearance between the body of the socket and the screw tabs in the box, and even though we put the deepest dual box in that's available, it was still tricky getting it in. And yes, we've noticed the socket is a different colour to the FCUs !

Untitled

• SimonH2
• 9 Sep 2012
• 1

 

[SimonH2]

Oh yes, I just moved the link so the fuse is after the switch and supply/load markings are correct.

 

[JohnW2]

Simon, was there perchance a wiring diagram that came with it?

Yeah, probably - but on the basis that when you've seen one instruction sheet for fitting a socket you've seem 'em all, I didn't actually look at it

Sure, but had it been me, I think I may have 'resorted' to having a glance at the instructions when I saw where they had installed the link ... as you will realise, my interest is in knowing whther they actually intended that the link be in that position (hence the fuse before the switch).

Kind Regards, John

 

[securespark]

And yes, we've noticed the socket is a different colour to the FCUs !

Untitled

• SimonH2
• 9 Sep 2012
• 1

It's a different range, no? The FCU's have black (or brown?) inserts, the socket white.

 

[SimonH2]

Same range, Dimension Screwless - seem to do white or black inserts but I can't see how the part number is coded !
Pages 7-8 in their catalogue

I didn't buy them ...

EDIT: On looking again I see it. The sockets are listed with white or black inserts, the FCU are black only.

 

[333rocky333]

And another point - what about unswitched fused spurs?

Even mk switched fused spurs appear to have the fuse before the switch
Indicators i assume are generaly wired across the double pole switch output and i I have yet to see any with indicators still lit with a missing or blown fuse

The one in the pic may be optional with or without an indicator hence the link