10A fuse ?

NC said the following on 09/01/2006 09:17:

or visit any local electrical wholesaler

Cheers. Searching for all sorts of key words on the RS website got me nowhere.... but the BS code did the trick. Thanks.

NC said the following on 09/01/2006 10:04:

You may have noted that RS incorrectly describe these fuses as 6.3x32mm in the one line description, but correctly identify them as 25mm long in the pop-up detail.

I didn't cite the RS reference to avoid confusion ;-)

If you take a bunch of 13A fuses you will find that the currents they actually blow has quite a wide variation, so all you need to do is select some which blow at around 10A.

;-)

make sure yout test it first

It probably is possible to correlate resistive impulse response to pulsed current, with blowing current, so you could make a good guess beforehand. However, 13A fuses are guaranteed to pass 13A forever, and none should blow at 10A.

The fuse in an FCU is simply there to protect the wiring after it. So even if using 1mm TW&E, a 13 amp fuse will be fine in most cases. If the 'appliance' needs further protection this should be done there - and say

Yep - I appreciate that - but just want to make sure everything is as it 'should' be. I will be routing the spur down into another room to provide power into a cupboard. PC & printer will be using that, plus a PC in the loft acting as a server. 10A will be sufficient, but I want to ensure that the 10A rating of the wire is not exceeded.

What wire are you using?

or cable ?

This was the subject of a fairly recent thread. He's got a fused spur run in 1 mm^2, so a 10 A fuse (for overload as well as fault protection) is the correct choice.

If running a spur from an FCU on a ring I'd just use 2.5mm TW&E. After all it's the one most people will have the most of lying around. Saves trying to be clever with non standard fuses or even having to think about such things.

Yes of course, or 1.5 even, which would still allow the full 13 A. And that's what the panel recommended he should do, but this had to be run through a confined space or awkward route and 'the designer' elected to use a smaller size.

:) I have routed 1mm^2 to the first double socket in the loft, and from there have taken 2.5mm T&E to another socket (dropping down inside wall space to a site in a cupboard). Protected using 10A FCU. Ideally would have been 2.5mm T&E all the way, but as someone has pointed out above, this wasn't possible.