Cooker Hood Connection

[AdamW]

Even as an 8 year old I knew not to do that, they showed us a video at school about the consequences of plugging extension leads into each other and using gaffer tape to fix wires together. Although the fuse in the first plug (into the wall socket) should blow before you cause damage. You can buy 12 way extension leads.

And Secure, did you have to balance the kettle on your head? The lead on mine wouldn't be long enough any other way!

As an aside, a multi-million pound military simulator made by my company was found to be malfunctioning because a squaddy plugged it into a dodgy 4 way extension lead! So if you have any hi-tech military equipment, I wouldn't recommend plugging it into a socket spurred off your cooker/electric shower/2A clock outlet.

 

[securespark]

Breezer

Doesn't matter whether there's two fuses or not, surely? As long as the whole lot is limited by a 13A fuse, you can have as many sockets as you like.

This method I have to resort to occasionally. Eg shopkeeper has counter with only a spur available. He wants many outlets for low powered things like tills and card readers etc... so I put in 3 doubles fed via 13A fused spur. Result, the load never exceeds 13A because the spur fuse will blow.

Most of the 30A accessories I have come across are designed for more than 1 6mm2 conductor.

Sockets too. They are designed for at least 2 x 4mm2 for rings with larger CSA cable.

 

[breezer]

you are right about the 2 fuses, i only mentioned it because most of mine have 2 fuses, and i was onlysaying yo could plug "4 way blocks" into each other and each other and so on, i didn't say you should

 

[ban-all-sheds]

...you cant tap off a shower or cooker cct becasue you wont get another cable the same size into the connections, and both these appliances are drawing Maximum load the cable will carry.

The problem of two cables into one terminal is a very real one, and many moons ago I was semi-idly toying with various ideas about how I could safely take a feed off a shower circuit for a fan. (I may have a solution BTW). As for the load issue, that isn't actually an issue - the cable (whatever size it is) is protected against overload by a fuse or MCB. If the "main" device takes it to the limit, then you won't be able to draw any more current for something else. If the main doesn't, then you will, and you don't need a special regulation to stop you having a shower and a fan, or a cooker and a hood for reasons of safety. If I had a 4mm radial on a 30A breaker, I could supply as many sockets as I liked, subject to a 75m2 floor area limit. And I could plug as many 3kW single ovens into each socket as I liked until the MCB tripped.

But I'm not using that argument to deny what the regs say - I've been there before and it does no good - if they say that if you replace just one of those sockets with a cooker control unit then all the rest become magically unsafe then so be it. (Also, being a gas-man, I've never wired a cooker unit - for all I know you can't get 2 x 4mm in, let alone 2 x 6mm)

in theory you could plug as many "quad" sockets into each as you like, so its one (4 sockets) 4 into each socket (16 sockets now, you get the idea)

if you were to plug something in too big (16 toasters) the fuse would blow,

here comes THAT word again, the regs say you cant do it on a normal radial because you only have one fuse (at the board) but by using "quads" each has two fuses (plug and quad itself) so each progressive "quad" has its own fuse just like using a bunch of fcu's

Except for 1 difference - you are allowed to use a gazillion cascaded quads, you're not allowed to use even 1 FCU.

If ever I find where my employer has hidden my copious spare time, I'll become a vexatious poster on the IEE site asking people to actually explain the logic behind some of their regulations.......

 

[AdamW]

so I put in 3 doubles fed via 13A fused spur. Result, the load never exceeds 13A because the spur fuse will blow.

I am only an amateur (a dangerous people!) but don't the regs limit you to 3 outlets (i.e. 3 singles, or 1 double and a single) from one spur? Yet you can just put another spur into the ring right next to the existing spur and get another three off that. The reasons for this are obvious.

I don't doubt that this is safe as they are unlikely to start plugging 3 bar heaters in around the till, but surely installing an extra spur would be in your business interests too?

 

[AdamW]

Or is the FUSED spur the key to this (i.e. as many sockets as you want because it is fused) and an UNFUSED spur can only have 3?

 

[ban-all-sheds]

If it's a spur off a 2.5mm ring, the limit is 2, I think, not 3 - one double or two singles, as that's 26A, which is OK for a single length of 2.5mm. Use an FCU, and you can have as many as you like.

Radial circuits will always be protected by device with an appropriate rating for the cable, so I don't think there are any restrictions on adding legs to a radial.

But I might be wrong, and it certainly looks as though in the case of a radial supplying a cooker or a shower, you cannot add anything to it.

 

[chester]

most helpful breezer...just wanted to check that if i just popped a plug on and plugged in my kitchen wouldn't explode!

thanks again

 

[securespark]

No, no no no no no NOOOOOOOOOOOOOO!!

You can only have one outlet on a spur, either a single or double socket or an FCU. Unless the FCU feeds outlets from the outgoing terminals, in which case you can have as many as you like.

See IEE on site guide:

"A non-fused spur feeds only one single or one twin socket-outlet or one permanently connected equipment"

"The total number of fused spurs (see below) is unlimited........."

"A fused spur is connected to the circuit through an FCU, the rating of the fuse not exceeding that of the cable, and in any event, not exceeding 13A"

IS THIS CLEAR??????????

 

[AdamW]

"A non-fused spur feeds only one single or one twin socket-outlet or one permanently connected equipment"

Just looked on screwfix and noticed all of the triple socket outlets have fuses built into them, obviously to comply.

 

[ban-all-sheds]

You can only have one outlet on a spur, either a single or double socket or an FCU. Unless the FCU feeds outlets from the outgoing terminals, in which case you can have as many as you like.
.
.
IS THIS CLEAR??????????

Indeed. I could have sworn I'd read somewhere that you could have 2 singles or one double, and this would be a perfectly logical rule. Bvggered if I can find where I read it though.....

 

[securespark]

Ban

Technically speaking, a 13A socket is just that, even a double ie you can only load a double up to 3120W safely. Guess what the regs are saying is a spur cable should only be loaded to 13Amps. I know what you're going to say, though.......!!

 

[ban-all-sheds]

Who, me??

 

[LifesABitchAndThenYouFry]

Breezer, Ban et al.......
Isn't it simply the case that being a radial circuit, you cannot tap off for anything else? That's how I understand it. Like a shower circuit. It's a radial only intended for feeding one appliance and nothing else.

It is acceptable to have two cookers fed off the same cooker switch as long as they are within 2m of the switch, alternatively a cooker and electric hob. The cable for both appliances should be same CSA as the circuit feed.

 

[securespark]

Adam W Yes I did, and now I have a bald patch........

Life - yes I should have mentioned the two cooking appliance exception to the rule. If you are allowed a freestanding cooker (hob oven & grill), then it makes sense that you are also allowed the equivalent in separate built-in appliances. Diversity applies in both cases, so electrically speaking they (an all-in-one cooker / separate appliances) are a similar load.