New CU

[Big_Spark]

so can you buy a consumer unit with RCBO's and MCB's already in. I've just had a quick look on tlc-direct but they are minus the MCB's. Know anywhere where they sell quality Consumer units, hager merlin green etc not wylex with MCB's and RCBO's already in.

No mate, I have never seen this except with the rubbish brands like Wylex, Contactum and Proteus, and they never include RCBO's, although I have seen them with an RCD main switch in a kit pack.

 

[ban-all-sheds]

Now it states REASONABLY, hence putting kitchen circuits on RCBO protection but not the lounge or hallway.

Mmm. I'd be surprised if I was the only person in the world who'd plugged a lawnmower or battery charger into a hall socket to use on the front lawn/driveway respectively...

Now, in Guidance Note 1, Selection and Erection of Equipment it states:

where socket-outlets can be deemed not to be used to supply portable equipment outdoors, or where this circuit may be used to supply electronic office equipment or similar then there is no requirement to afford this circuit the protection of a residual current device or RCBO.

Ah - so what's the rule for a garden office full of electronic equipment?

(No - I'm not being pernickety - garden office full of stuff is on the schedule for this year....)

 

[journeyman]

One ring circuit for the kitchen may not be enough:

Washing machine
Dish washer
Tumble dryer
Combination Microwave
Fridge Freezer
Toaster
3Kw kettle.

This adds up to more than 32A at full load. It is not likely that all appliances will be on at once, though it is possible in a busy household.

My house (built 3 years ago) has a separate circuit for the fridge, washing machine and cooker hood. It has a 32A RCD. Two 2.5mm cables going to a three gang grid switch. Three single 2.5mm going to single unswitched sockets.

Is it a ring with spurs or is it a radial with reduced current carrying capacity on the parts after the switch and parallel conducters for the parts before the switch?

Maybe I should ask Schroedinger's cat.

 

[BR]

So BR, next time you wish to say I am talking ****, get off your fat **** and actually do some research before commenting. You are certainly a case of the Pot calling the kettle black.

I apologise to the others for this last little outburst, but I am getting tired of slackjawed wannabe's from slagging me off when they don't fully know what they are talking about.

slackjawed wannabe? I'm a qualified industrial electrician of 25 years experience! have designed more factories, shops, schools etc. then i care to remember and you have the cheek to refer to be as that! Well.............

 

[journeyman]

Now it states REASONABLY, hence putting kitchen circuits on RCBO protection but not the lounge or hallway.

This is why arguments start. The regulations use the word reasonable. This is open to interpretation.

My house has a front lawn. I have no external sockets for the purpose of plugging in a lawn mower. What am I likely to do?

i) Plug the lawn mower into a kitchen socket (RCD protected) and trail a lead through the hallway.

ii) Plug the lawn mower into the hallway socket (non RCD protected) near the front door.

Answers on a postcard please.

 

[Big_Spark]

slackjawed wannabe? I'm a qualified industrial electrician of 25 years experience! have designed more factories, shops, schools etc. then i care to remember and you have the cheek to refer to be as that! Well.............

As an ELECTRICIAN how much of the design did you really do, or did you simply help to install it?

I don't know of many electricians that are involved in the design of installations, not in the UK or other countries, except perhaps for the local rewire or simple new build.

Most Local Authority work will go through Chartered Engineers and the same will certainly be true for Industrial settings.

BTW...slackjawed wannabe was a bit OTT...

 

[bignev]

I'm going to split the kitchen and utility from the downstairs ring. Whats the way to do it (please agree). Does the Fridge/freezer go on its own ring or is it a spur.

I'm also going to put a separate box in the garage/studio, with an outside socket as a spur.

 

[Big_Spark]

Nev, the Fridge/Freezer could be put on a Radial specifically for that and protected by a normal 16A Type B MCB, that way the reat can be either RCD or RCBO protected at your discretion.

The most likely culprit for causing nuisance tripping in a home is the Fridge/Freezer, singular or combined. Stop that and most of the Nuisance is got away from and the rest can then be put on a 30mA RCBO..

I have had a hunt since my original post, it woul be hard for you to buy a Type B 100mA RCBO, the cheapest I can find them is over £70 each, that is almost TWICE the price of the 30mA version.

 

[bignev]

£70 is a bit steep. So a 30 it is. Do I split the existing ring with junction boxes and take these back to the CU

 

[Big_Spark]

£70 is a bit steep. So a 30 it is. Do I split the existing ring with junction boxes and take these back to the CU

If there is no way to simply wire a new circuit in without major works, then you can do it that way, so long as the JB's are under the floor.

 

[il78]

Now it states REASONABLY, hence putting kitchen circuits on RCBO protection but not the lounge or hallway.

This is why arguments start. The regulations use the word reasonable. This is open to interpretation.

My house has a front lawn. I have no external sockets for the purpose of plugging in a lawn mower. What am I likely to do?

i) Plug the lawn mower into a kitchen socket (RCD protected) and trail a lead through the hallway.

ii) Plug the lawn mower into the hallway socket (non RCD protected) near the front door.

Answers on a postcard please.

buy one of these

 

[Big_Spark]

I think what this discussion has showed, above all else, is that quite often people do not consider an installation fully before undertaking the work.

You need to know everything about it and how it is likely to be used before you can design the installation. Journeyman highlights a valid point,and a piont that causes many sparks to put all sockets on RCD/RCBO protection, the problem is this is done without consideration to other influences on the installation, one which are actually there all the time and not once every so often, as in the case of mowing the lawn.

This is one area that the IEE MUST deal with, it has been a grey area for 20 years and it is about time it was made black and white.

 

[bignev]

Guys,

thanks for all the help so far but here's another one. A chap a work has just offered me a Hager 14 way box. He's giving it away, but I don't know how old it is. It takes type 2 mcb???? and has 32,15,10 and 5 amp mcb. I guess its a few years old and I may be better off purchasing a new one. But worth a thought. By the way what are type 2.

Thanks

 

[Big_Spark]

Nev, the NEW Hager kit is good quality, but their older stuff was less than impressive, unless your really stuck for cash, I'd say thanks but I'll pass.

Ideally all the breakers should be changed anyway, you have no idea the stresses they have been subjected too in the old installation and they may be prone to nuisance trip..a real pain.

Type 2 is OLD, they are now called Type B, C or D, and this refers to the momentary loading they can handle before operating.

In your home, all your breakers should be Type B, they should never be C or D.

 

[ban-all-sheds]

In your home, all your breakers should be Type B, they should never be C or D.

What's your recommended cure for nuisance trips of Type B breakers on lighting circuits when lamps blow?

1) Use a bigger rating
2) Use a Type C
3) Go back to using fuses
4) None of the above - just put up with it