Search results for query: the fuse is to protect the cable

Fuses etc. are to protect the cable - nothing to do with what's connected to it.

I was looking at getting the shed wired up...yes I know old topic lol anyway I notice that the main incoming fuse before the meter is 60A but the main breaker in the CU is 100A. I'm not too hot on discrimination calcs (I'm and electrician but don't do installation work) but I'm guessing that...

the cpc protects the fittings and the cable. if you cut a live cable with cpc it is protected and the fuse or mcb would blow. if you cut a live 2 core switch wire with no cpc (or neutral) the fuse or mcb wouldn't blow.

The fuse is not for the transformer which should be internally protected. It is to protect the cable.

dpm - FYI the main purpose of an FCU is to be able to "fuse down". i.e you have an extractor fan supplied via a 16 amp radial circuit and the manufacturer states it must be protected by a 3amp fuse. you would connect the 2.5mm cable to the FCU and the cable for the extractor to the load side...

What seems common is to state the fuse protects the cable. As to the connector on the end of that cable to me they should also be protected by the fuse. So a 2.5A connector even if moulded onto a 1.25mm² cable should still have a 2A fuse not a 13A fuse even though a 13A fuse would protect the...

Justin, With regards to wanting written evidence - Are you overthinking this? You have a 13A fuse, 2.5mm2 cable, and 8 sockets. Your setup is the same setup as this (in fact yours is better as you have better cables, and sockets). : The 13A fuse in the plug/FCU will protect the 2.5mm2 cable...

The RCD will only protect the appliance that is plugged in to it. So if you are installing new cable, you need to protect that by means of either a RCD protected fuse connection unit where the new cable starts if adding to an existing circuit or RCD protection at the board.

Hello everybody, I have a modern central heating system, protected at a FCU with a 3 amp fuse, this in turn is supplied from the CU on its own mcb radial circuit,.....but the mcb is 20 amp and cable is 2.5 T&E, there are no problems, but should it be a 6amp mcb with 1...

They don't state a fuse size and they should not be relying on the fuse in the plug for protection. It exists solely for the protection of the cable (and, unfortunately, the regs have a giant loophole which means almost every cable is 'protected' by a 13A fuse).

Thanks Damocles. That old anomaly makes sense now. I suppose the same rule applies to the armoured cable coming into the house. From what I've read elsewhere on this forum the substation fuses could never protect this against overload. That job is left to the 60 amp fuse at my end.

PLease stop posting this misleading and very dangerous advice. Appliances have cables between the plug and the appliance that need fuse protection. You are telling people these cables do not need protection.

no breezer, i have to disagree with you here. i don't see how this would cause an accident. as long as the cable is fused along its length, it is being protected. it won't carry any more current than it is designed for - the current has to go through the fuse. therefore there is no risk of...

It can be safe, provided that BOTH outputs are taken downstream of a 5 amp fuse inside the FCU, as the 5amp fuse will protect a 1mm cable adequately (remember lighting circuits on 1mm cable used to be on 5amp wire fuses!)

Fuses etc. are to protect the cable, not the appliance. If you connect it to the "lighting" circuit, you will not need a fuse at all, just a switch.

What value is the protective device (ie fuse) for teh shower? What size cable connects the shower to the fuse board?

If the boiler is connected through a fused connection unit, check the fuse. It might be 3A, which can protect smaller cables.

Why doesn't he just replace the double socket with a single 13Amp fused connection unit and run the flex cable from that? That way the flex cable is protected by the 13Amp fuse.

This one will probably wind up a few sparks here! I am moving the switch for my immersion heater from one side of my airing cupboard to the other. On inspection of the existing cable it turns out the immersion heater is supplied by a 4.0mm2 radial. This radial is protected by a 15A rewireable...

Apart from the fact that the assertion that "fuses are used [only] to protect the cable" is debated even in the UK, I, for one, do not know whether that same view/concept exists in other countries. Why, I wonder, in the UK is their an upper limit to the rating of OPD allowed on a lighting...