Recommendations for an external double socket

[ey143]

Hi

Could I please have some recommendations for an external double socket - good quality one.

I have bought these ones off Amazon in the past, but they are so difficult to clip the plug guard down.

https://smile.amazon.co.uk/gp/product/B006GAETZU/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Also are there sockets which are flash mounted rather than surface mounted, or is it for water protection purposes that are surface mounted?

 

[flameport]

The BG ones are about as good as they get.
They all have substantial clips to hold them closed, they wouldn't be much use at keeping water out otherwise.

It's this one: https://www.screwfix.com/p/british-...dp-weatherproof-outdoor-switched-socket/67928
rather than the type with the useless RCD in it.
Circuit should already have RCD protection, and if it doesn't, an RCD will need to be added.

MK make flush mounts for their grossly overpriced Masterseal range, but they are designed for tiled or other flat finished walls and not for general outside use.

 

[briwire]

I fitted one of these yesterday. I agree that the clips are a bit tricky. There is a knack, when opening you have to press the tap up as instructed but with the other hand pull the two claws towards you so you are doubling the force used. Opposite operation when closing. As said above, they have to be watertight.

 

[ey143]

How do you run your cables? Do you have an external switched power socket like this one https://smile.amazon.co.uk/gp/product/B08JMBDK9R/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1 or do you just run it of the back of an existing internal socket ring main and poke through the wall?

Also, I plan to install a few externally at about 3m high to prepare for an external sun blind which will fold out with the use of a motor so have been told that the thing is powered via a 3 pin plug which needs to be near by. As this will be under the parapet wall, if water ever comes dropping down or even pours over it, will the IP66 be more than capable of protecting the inner bits?

 

[blup]

I fitted mine as an extension to the existing ring main from an internal double socket.
Used the MK masterseal (active), quality is good.

Blup

 

[ey143]

By the way, is there ANY upside of having an RCD on the socket if the main consumer unit has a RCD protection on there. Does it for example, trip the socket RCD without tripping the consumer unit and other circuits in the house that way>

 

[Jon c]

By the way, is there ANY upside of having an RCD on the socket if the main consumer unit has a RCD protection on there. Does it for example, trip the socket RCD without tripping the consumer unit and other circuits in the house that way>

No, there is no point at all having an RCD socket if the circuit already has RCD protection. It is just one more thing to go wrong and annoying to have to reset each time before use. I have the BG one and it's good, yes the clips are tight but they need to be to keep it waterproof.

Edit: It is pot luck which RCD would trip first if both the socket and consumer unit had one.

 

[ey143]

From a technical point, why wouldn't the RCD socket trip first? Also it's more convenient to trip the socket rather than the whole ring main circuit at the consumer unit and have to walk into the house if it trips because e.g. you were mowing the lawn (as it happens sometimes when the motor cant take it due to lengthy grass).

 

[flameport]

With two RCDs on the same circuit, it's just a question of which one is faster at tripping, most of which is due to the mechanical components of the device.
There is no way to know or predict which will trip first, and in some cases both will trip.
The only way is to have one RCD with a time delay, that delay being longer than the longest trip time for the other RCD - however that is not suitable for or applicable to circuits supplying socket outlets.

An RCD does not detect overloads, so a stalled motor won't cause it to trip.

The standard for RCD socket outlets states that they are not suitable for additional protection and are intended to be used where there is already some other RCD protection for the circuit, which makes them totally pointless.

 

[Jon c]

From a technical point, why wouldn't the RCD socket trip first? Also it's more convenient to trip the socket rather than the whole ring main circuit at the consumer unit and have to walk into the house if it trips because e.g. you were mowing the lawn (as it happens sometimes when the motor cant take it due to lengthy grass).

Consider the two types of fault an RCD trips for.
A 30mA RCD will actually usually trip at around 23mA but the socket RCD and house RCD will trip at slightly different values, so the one with a lower value would trip first if you have a small leakage fault (such as water between live/neutral and earth)

For a large leakage fault (such as neutral to earth direct short) it just depends which RCD happens to have a faster tripping time. Again the time value will be slightly different for each RCD, so whichever happens to trip faster will trip first.

If both RCDs happen to have very similar values for time and mA to trip, its possible that both would actually trip simultaneously.

 

[ey143]

Ok, noted thanks.

And in one of follow on questions above, I was asking about an IP66 rated switch. Do people ever use switches inside or outside to switch off power going to an external double socket? And would the socket in theory still be safe if water poured on it from a parapet wall (poured is a huge exaggeration but just trying to understand if placing the socket so high under a coping stone on a parapet wall will be an issue).

 

[Jon c]

Ok, noted thanks.

And in one of follow on questions above, I was asking about an IP66 rated switch. Do people ever use switches inside or outside to switch off power going to an external double socket? And would the socket in theory still be safe if water poured on it from a parapet wall (poured is a huge exaggeration but just trying to understand if placing the socket so high under a coping stone on a parapet wall will be an issue).

It's a good idea to have a double pole switch inside to isolate power to the socket in case it fills up with water or something which would trip the RCD, so you can switch it off until its repaired and reset your RCD. In an ideal world it would be nice to run a circuit to the socket from an RCBO in the consumer unit so nothing else is affected if you have a fault outside, but clearly that's not easy in most houses, and would be notifiable work.

In theory it should remain safe if water is poured on it as long as its installed correctly and the lid is latched shut. But it wouldn't be advisable to install it in a location where it would get unusually wet. Make sure you seal the rear entry hole well with silicon as well as running a bead of silicon at the top and sides of the socket box once it's installed on the wall, but DON'T seal the bottom so that water can get out if any manages to get in.

 

[ey143]

It's a good idea to have a double pole switch inside to isolate power to the socket in case it fills up with water or something which would trip the RCD, so you can switch it off until its repaired and reset your RCD. In an ideal world it would be nice to run a circuit to the socket from an RCBO in the consumer unit so nothing else is affected if you have a fault outside, but clearly that's not easy in most houses, and would be notifiable work.

In theory it should remain safe if water is poured on it as long as its installed correctly and the lid is latched shut. But it wouldn't be advisable to install it in a location where it would get unusually wet. Make sure you seal the rear entry hole well with silicon as well as running a bead of silicon at the top and sides of the socket box once it's installed on the wall, but DON'T seal the bottom so that water can get out if any manages to get in.

Thanks, good points.

 

[EFLImpudence]

There are advantages with an RCD socket which has an 'active' RCD (house ones don't).

This means that it will trip when a power cut happens so that the tool being used when the trip occurred does not automatically burst into life on resumption of power, and (some or all?) will trip if the earth wire becomes disconnected.

 

[ey143]

There are advantages with an RCD socket which has an 'active' RCD (house ones don't).

This means that it will trip when a power cut happens so that the tool being used when the trip occurred does not automatically burst into life on resumption of power, and (some or all?) will trip if the earth wire becomes disconnected.

1. What do you mean by active rcd?
2. I'm having my house rewired as part of a renovation. I presume the different areas/ring mains of the house will be on an RCD. Are you implying that if there is ever a power cut and I'm on holiday, my chest freezer and normal fridge/freezer will not return to an on-state?