Double socket off a 13a fused switch?

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While fitting our new kitchen i replaced a single unswitched socket for a double unswitched socket so that i could run a tumble dryer and washing machine from the same 13a fused spur. That fuse in the spur has just gone. I've replaced the fuse and its working again but is a dryer and washing machine likely to be too much for the spur/fuse?
 
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It’s too much for 13A when on together

It’s also not sensible for them two items in the same double.


Some replanning required.
 
While fitting our new kitchen i replaced a single unswitched socket for a double unswitched socket so that i could run a tumble dryer and washing machine from the same 13a fused spur. That fuse in the spur has just gone. I've replaced the fuse and its working again but is a dryer and washing machine likely to be too much for the spur/fuse?

Why is the socket on a fused spur? There may be a good reasons such as a spur on a spur, but often for some reason people use a fused spur for a washing machine socket when a double pole switch is all that is needed.
 
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Why is the socket on a fused spur? There may be a good reasons such as a spur on a spur, but often for some reason people use a fused spur for a washing machine socket when a double pole switch is all that is needed.
I agree that a FCU is not required if it is feeding a socket for an appliance. But I always do(and I think it tends to be done this way by most) as I have too much experience of exactly the scenario outlined in the OP.
I found one situation where a single socket had been changed to a double and had 2 (unfused) adapters with 4 appliances plugged in.
 
I found one situation where a single socket had been changed to a double and had 2 (unfused) adapters with 4 appliances plugged in.
But that could be done with any socket on the ring, and create problems.

There's no guarantee that the cables supplying any socket on a ring have as high a current-carrying capacity as a single 2.5mm² spur cable if the installation methods are different.
 
But that could be done with any socket on the ring, and create problems.

There's no guarantee that the cables supplying any socket on a ring have as high a current-carrying capacity as a single 2.5mm² spur cable if the installation methods are different.
I thought all the derating factors had been taken into account, is this not so?
But at least it will have 2 cables feeding it. And this is exactly why I believe spurs should be:
A) not allowed, or
B) fused down, or
C) use a bigger cable.
 
I thought all the derating factors had been taken into account, is this not so?
Not sure what you mean.


But at least it will have 2 cables feeding it.
Which may (allowably) have a CCC of only 20A, whereas a 2.5mm² spur cable from the same circuit might be 27A.


And this is exactly why I believe spurs should be:
A) not allowed, or
B) fused down, or
C) use a bigger cable.
Would you do that via a special removal of compliance with the general regulations on fault and overload protection, or would you change those fundamental principles?
 
Not sure what you mean.



Which may (allowably) have a CCC of only 20A, whereas a 2.5mm² spur cable from the same circuit might be 27A.



Would you do that via a special removal of compliance with the general regulations on fault and overload protection, or would you change those fundamental principles?
I have gone through life under the impression that the ring final is a predetermined installation method which has all the circuit design principles taken into account including but not limited to derating factors.

It's perfectly feasible that a full load of 32A may be applied at any point of a ring, by that I mean there may be several sockets in close proximity with heavy loads, such as the kitchen. Are you saying this may be outside of the design parameters and therefore unsafe?

I would do this by applying circuit design principles, I would not consider a 2.5mm² radial on a 32A OCD to be a sensible design even if it only had a single 13A fuse on the end of it, however the blasé addition of such to a ring is considered to be conformist and safe. Indeed I have several incidents of such in my home, as it happens far fever than when I purchased but that's a different story.
Before anyone starts describing downstream fusing, I am very familiar with the principle within my control panel experience.
Do away with rings, then you can call the spurs something else - namely branches.
I do have some sympathy with the dislike of rings, however I personally have not encountered any significant problem in the 50 years I've had involvement with them. As such I have no real axe to grind for removal. As it happens I have recently changed 4x16A radials to 2x32A rings to upgrade stage lighting in a village hall.
 
It's perfectly feasible that a full load of 32A may be applied at any point of a ring, by that I mean there may be several sockets in close proximity with heavy loads, such as the kitchen. Are you saying this may be outside of the design parameters and therefore unsafe?
To put this into context, I find that many new builds have a 12way grid plate with 6 switch & 6 fuse modules as the significant, if not total, load on a ring final.
 
I agree that a FCU is not required if it is feeding a socket for an appliance. But I always do(and I think it tends to be done this way by most) as I have too much experience of exactly the scenario outlined in the OP.
That potential problem surely goes away if one installs a single socket for the appliance - in which case an FCU supplying it is certainly not needed, given the fuse in the {one and only} plug.

Kind Regards, John
 

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