13amp v 3 or 5amp

Seve OB

My daughter got a strip of LED lights she wants to stick up in her bedroom.
It came with a transformer thing for the power and a separate 2pin power cable that goes into that with a 13amp fused plug.
The power cable is not long enough. I have load of them lying around but they all have different fuses in them.
Do I need a specific lead with a 13amp fused plug or could I simply swap the fuses over?
Or would it work just as well with a 3 or 5 amp fussed plug?

Thanks for help

aido79

Seve OB wrote: »

My daughter got a strip of LED lights she wants to stick up in her bedroom.
It came with a transformer thing for the power and a separate 2pin power cable that goes into that with a 13amp fused plug.
The power cable is not long enough. I have load of them lying around but they all have different fuses in them.
Do I need a specific lead with a 13amp fused plug or could I simply swap the fuses over?
Or would it work just as well with a 3 or 5 amp fussed plug?

Thanks for help

What wattage are the lights? What's the output of the transformer?

Seve OB

Transformer is 12v

Can’t see any wattage indicated

Seve OB

First picture is the transformer I mentioned. The lead in question goes from here with a 13 amp fused plug, which I have at the moment swapped out for a 3amp one

Second picture may mean something, transformer lead plugs into this box, it has the lights plugged into it and a remote control sensor for operating

aido79

Seve OB wrote: »

First picture is the transformer I mentioned. The lead in question goes from here with a 13 amp fused plug, which I have at the moment swapped out for a 3amp one

Second picture may mean something, transformer lead plugs into this box, it has the lights plugged into it and a remote control sensor for operating

The worst thing that can happen is that the 3 amp fuse blows. It shouldn't happen though if it's just an LED strip.

AutoTuning

Input label says is rated 1.6 amps. 3amp fuse on mains cable is appropriate.

Also IEC "figure of 8" 2 pin connectors are only ever rated for up to 2.5 amps, so 3 amp fuse is appropriate.

TheChizler

Strictly the fuse in the plug is to protect the cable not the device, so should be sized for the cable. I wouldn't go swapping fuses unless you put the plug on yourself at some point.

AutoTuning

If it's going into an IEC C7 connector it's 2.5amp rated. That's the lowest common denominator on that cable.

3 amp plug fuse is appropriate.

They're used with unfused plugs on 16 amp / 20 amp circuits all over Europe, so it's not exactly a massive risk with a 13 amp fuse either. But, if you are doing things as safely as possible, use the lowest rated fuse.

The worst that can happen is the fuse will blow too easily, causing minor annoyance.

Seve OB

Thanks guys

adrian92

AutoTuning wrote: »

Input label says is rated 1.6 amps. 3amp fuse on mains cable is appropriate.

Also IEC "figure of 8" 2 pin connectors are only ever rated for up to 2.5 amps, so 3 amp fuse is appropriate.

I think that you should install 5 amp fuse for the following reasons;

13 amp do not work, never provide protection
3 amp fail with no electrical fault, maybe too frail

Treseemme.

adrian92 wrote: »

I think that you should install 5 amp fuse for the following reasons;

13 amp do not work, never provide protection
3 amp fail with no electrical fault, maybe too frail

A lot of truth in that imo

Anyhow the 13amp plug and socket is a bad system

AutoTuning

The alternative, as used in all other systems, is you don't provide local fusing at all. It's just a 15, 16 or 20 amp circuit with unfused plugs in the US, Continental European systems, Australia/NZ etc

The main reason for the fuses in the UK plug system used here in Ireland is that they allow ring circuits - a socket might only be protected by a 32amp circuit breaker or fuse on the distribution board. That necessitates local fusing on plugs or in fused connection units.

The 3amp fuses were just a supplemental measure that allows a bit of extra protection for thin flexes. In the 1940s when that system was introduced, thin, fabric coated and braded flexes were common on lamps and radios etc. If you've ever seen an old small appliance, the flexes were often zip cord or very thin and single insulated stuff, often with little or no fire resistant. In the event of an over load they could catch fire. That's why the plug fuses were brought in.

The old British system with round pin plugs had a mess of about 6 or more incompatible 2 and 3 pin plugs rated from 2 to 15 amps and the circuits had to be fused accordingly. So houses often had all sorts of messes of adaptors. At the time Ireland seems to have either used the continental system; side earthed 16 amp sockets, or mostly just the 3 pin 15 amp UK round pin sockets. We rarely seem to have used the extremely over complexity mess of plugs the UK used to have.

The reality is all flexes and appliances sold in the EU since the early 70s are safe to operate on an unfused and unpolarized continental plug and socket system, protected by just the circuit breaker, if it's a radial circuit and appropriately rated. Running unfused plugs on ring circuits, which are the norm in Britain and used here but to a lesser extent, would be a serious fire hazard.

In general though, I'm not seeing what's bad about an extra fuse in the plug. Even on a socket on a 20A radial circuit, it's an additional layer of overcurrent protection.

If you just pick the fuse to be slightly higher than the maximum load expected on the appliances, you're extremely unlikely to ever see it blow.

Also plug fuses tend to operate slowly. In a short cuircut, I've never seen one blow. The MCB has always tripped much faster, even though it's rated at 20 amps.

Treseemme.

That's true about the ring circuit and plug fuses

Not sure about the fire hazard with unfused plugs though

The leads are sized to match the loads, I don't think the overcurrent protection is even there with 0.75 flexes and 13amp fuses

AutoTuning

There’s a fire hazard using unfused plugs on ring circuits. That’s mostly why the design tries to prevent jamming in Europlugs.

The fire hazard with thin flexes was likely more of a concern before the 1970s. There were a lot of very light flexes used, particularly in the U.K.

If you’ve ever seen a vintage lamp, you’ll see absolutely minuscule conductors and often a cotton braded flex or flimsy plastic coated single insulated flex, prone to splitting in insulation- that could catch fire in theory.

I just find a lot of British stuff seems to be odd solutions in search of problems though. There isn’t an issue with millions of Swedes, Germans, Americans and Australians being incinerated by unfused plugs.

It’s the same with the fixation on never installing mixer taps, in case the water somehow mixed. There used to be some rule that prevented it and the kitchen taps had two nozzles on the top that provided hot and cold streams side by side! That never seems to have applied here, but common in England. You get scalded and frozen by each half of the stream of water.

Just a lot of problems that seems to exist only in theory and only in Britain.