New kitchen sockets .. SP or DP ?

[EFLImpudence]

Save a lot of argument

 

[crystal ball]

Save a lot of argument

Well it is double pole

 

[JohnW2]

Obviously you could. ... Some less intelligent, may just turn them off.

Then, in the situation you're envisaging, they would not solve the problem, and would pay the price for their 'less intelligence' by having to call out an electrician.

Do you think that light switching should all be DP (will all the modified wiring that would entail) in case a ceiling rose filled up with water and tripped an RCD (and, yes, I have experienced that - more than once)?

Kind Regards, John

 

[danechip]

"Assuming" the socket is wired correctly, what is the issue with a single pole? Fusing the neutral has been gone a long long time, why the need to isolate it too ?

 

[JohnW2]

I would always go for DP, if we go on holiday I always unplug every appliance apart from the fridge freezer, if its a short break .... Well it is double pole

Fair enough, but we're talking about DP switching - not DP isolation by unplugging plugs

Kind Regards, John

 

[JohnW2]

"Assuming" the socket is wired correctly, what is the issue with a single pole?

As I've said, I personally see no issue with SP (i.e. no advantage of DP). If people are so daft that they don't try unplugging an appliance which they think may be the cause of an ongoing RCD trip, then I reckon they deserve to face an electrician's bill!

Kind Regards, John

 

[danechip]

but certainly no disadvantage.

There is, more mechanical parts to fail in my opinion.

 

[JohnW2]

There is, more mechanical parts to fail in my opinion.

Yes, I suppose that is true - which really reinforces my view.

Kind Regards, John

 

[sparkwright]

The problem with double pole switches is when they go wrong.

You could find yourself in a situation where the live is continuous, and the neutral is broken, and the switch appears to be in the off position.

In this situation, the appliance does not 'work', so you think it's isolated - but there is electricity running through the live wire.

This is more of a problem on 'fixed' wiring, during a repair to the appliance - fortunately pulling the plug on a plug-in appliance would be the procedure before an appliance repair.

 

[plugwash]

I struggle to think of any advantage in having a DP switch in a socket.

If a fault develops in an appliance while the socket is turned off then with a SP switch it may trip the RCD immediately, with a DP switch it won't trip the RCD until you turn it on. This may make it more obvious which appliance is responsible for tripping the RCD.

If someone is stupid enough to work on an appliance while only switched off at the socket, then a DP switch leaves them protected from neutral faults. OTOH a DP switch could conceal a potentially dangerous fault if it's live pole fails closed while it's neutral pole continues to operate.

In practice though, I think the practical differences are pretty marginal. The only appliance I can think of that I routinely switch off at the socket is my George Forman Grill, and if i'm going to work on a portable appliance it's getting unplugged first.

 

[JohnW2]

The problem with double pole switches is when they go wrong. ... You could find yourself in a situation where the live is continuous, and the neutral is broken, and the switch appears to be in the off position.

Indeed - and when that happens, it's somewhat analogous to having neutral fuses - which we know is a very bad idea.

Kind Regards, John

 

[Nozzle]

Of course some outlets have no switch at all, but still, there they are!!

Nozzle

 

[Risteard]

I always use DP socket-outlets (other than unswitched ones obviously). No benefit to single pole to save pennies.

 

[OwainDIYer]

AFAIK the only restriction is that a central heating boiler cannot be plugged into a switched socket.
Must be an unswitched socket or a fused connection unit.
This is so that L+N isolation is assured, by pulling out the plug or switching off.

 

[EFLImpudence]

There is no such restriction.