First of is this fine to do as a DIY'er or is it part P and second can you have it run of an indoor socket as a spur. Thee other ting is what is the difference between an active RCB socket http://www.screwfix.com/p/mk-masterseal ... tive/26746 and a passive RCB socket http://www.screwfix.com/p/mk-masterseal ... sive/76855. Which of them are better or am I just aswell to go with this slightly cheaper one http://www.screwfix.com/p/nexus-2g-13a- ... cket/91095. The last thing is if it is possible to run it as a spur of another double socket inside and is do able by a DIY'er how can I get the cable around a corner as the double socket is on the other wall not the wall the outside socket will be mounted to. I will try and get a picture later to show you what I mean. Thanks in advance.

Right can't get my digital camera to work but I did a quick doodle of what i mean on paint, the red box would be the outside socket and the litle black square is the double socket inside and the pale blue rectangle is the patio door. Also I think I found out about the passive and active sockets and I think I need a passive one for strimmers and shreders etc.

An active RCD will drop out with power failure a passive RCD will not. The problem with many RCD's is they require a voltage to work so if the loop impedance is below a certain level under fault conditions the RCD can fail to operate. So at the consumer unit we will normally use a passive RCD as the loop impedance is low and it is unlikely the voltage will drop below the threshold due to a fault. But with a plug in type is could be used at the end of a long extension lead so we want it to fail safe so an active type is used.

For sockets on a ring main it would depend on loop impedance as to if it would be safe to use a passive type. So in the main we use active types.

As to the law and Part P you are allowed to use pre-wired kits but fitting any other fixed electrical installation without notification is in the main not allowed. Personally I would be more worried about what's safe than what's the law allows.

Once one leaves the bonded area of the house the protective devices may not work. There are a host of rules about earthing methods and loop impedance requirements and in the main the trained electrician will by simply looking at the job realise where there is likely to be a problem. Using a RCD was the common method of playing safe. I say was as now all sockets inside or outside under 20A have to be RCD protected except for some specials like those supplying a freezer. Also all buried cable under 50mm also needs either to be special cable or RCD protected so in the main the RCD's are now part of the consumer unit.

With this in mind where as yet the consumer unit has not been updated then it would be prudent to use a RCD for outside use which would still be of some use after the upgrade. So using a 10ma Active RCD for outside would seem to be the way forward.

However they are expensive and I would tend to go for the cheaper plug in units. There was a plug-in 10ma unit available but looking at the site it's no longer listed.

So it comes down to price. And you ask about the law so I will assume you will register the work and pay the council fee and also hire the test equipment so you are looking at £200 to DIY which means likely cheaper to get an electrician who is a member of a scheme and can self certify to do the work. So all I have said my be interesting but not really any use to you as the electrician will select the best method.

How much roughly would an electrician charge to install one of the sockets I asked about, so for strimmers to shut of etc in emergency and need passive one.

Personally I would use a plug in unit or have then installed into the consumer unit. I see no real point in RCD sockets as very expensive for a temporary until done proper. Likely most people will at some time want things changing in their house and to use Ali-tube cable to supply RCD sockets around the house is an expensive way of doing things.

At the moment in this area one can't buy the odd lenght of Ali-tube cable and to buy a whole role is expensive. So likely the socket you want to take supply from would need changing to a RCD fused connection unit (FCU) to protect the cable feeding the outside socket. This will likely mean you lose the socket inside.

Although I don't like them Blagdon do make kits to power outdoor items it's called Powersafe you will notice these still use plug in RCD units. If you really want to DIY then I suppose that's the way to go. But as to price to do a proper job you will need to get a quote from a local man as there are so many things what can impact on the price.

Eric could I have a normal out door socket fitted without messing with the house wiring and when using the strimmer or power tool use a plug in rcd. If this is a case do electricians normaly like to use there own product or could I buy one and have them fit it, as we are having an electrician to fit a socket on our work top

Personally I like the idea of plugging in outdoor equipment as it can be unplugged with easy when anything goes wrong and one has no worries about neutral earth faults tripping the RCD. However not really a professorial approach and I would not expect any electrician to do it that way.

As to parts supply always let the electrician supply and fit. The problem is where you supply should anything go wrong with the items then you pay for the electrician to change the item. The electrician buys at trade and sells at retail and that profit pays for his time should he have to remove and replace any faulty item.

It is always a problem where you have more than one person responsible for an installation. I have seen it many times. The electrician says it's the plasterers fault and plaster says nothing to do with him it's electric. If both employed by a builder then not your problem the builder sorts it.

I am sure you can see the reasoning.

The plug in RCD has one problem. It can be unplugged. If your doing the job clearly you will not unplug it. However where an electrician is doing the work he has to consider it could be unplugged.

Most of the rules refer to using a key or tool. Reading 411.3.3 which is the regulation and states:- In a.c. systems, additional protection by means of an RCD in accordance with Regulation 415.1 shall be provided for:
(i) socket-outlets with a rated current not exceeding 20 A that are for use by ordinary persons and are intended for general use.

Although no reference to a tool or key I have reservations as to if using a plug in RCD would comply or not! I have in the past done things like put a tie rap which needs cutting to open or remove something. This means one needs a tool (Pair of snips) so will comply.

However it will be up to the electrician doing the job as to what he feels will comply. He signs paperwork so it's his call.

There is no longer a special requirement for outdoor sockets to be RCD protected as now all sockets under 20A need to be RCD protected. (With some special exceptions like supply to fridge)

So some electricians will follow the rule book closer than others. So it's no good me saying what he will do you have to ask the guy doing the job.

I'm not quite sure what you mean, it would be a 13amp outdoor socket and a rcd that fits on to the strimmer, something like this
http://www.screwfix.com/p/masterplug-rcd-adaptor/63731#
or this
http://www.screwfix.com/p/rcd-adaptor/15263

either of those should protect you if you cut the cable,

if your really stuck for options, there is this kit from screwfix
http://www.screwfix.com/p/nexus-outdoor-power-ip66-socket-kit/78690 - item 78690

its an outdoor "extention lead" that comes with an flex and indoor RCD plug

going by the trend of the thread this should be acceptable for exclusion from Part P ?