muffster

A quick question please.
Does any of you electrical peeps know where i can find an online diagram or a good description on how to wire up a consumer unit.
Iv'e put a small consumer unit into my campervan, i think iv'e done it correctly but i obviously want to be sure.
Iv'e spent ages trawling t'internet tonight but no joy. The bit i'm most concerned with is the supply from the unit to a 2 gang DP switched socket.
Many thanks.
Muffster.

danneth

i would get it checked out properly mate, but failing that anychance of putting some piccys up?

muffster

Not a bad idea mate but im away at work at the minute!!
Are you an electrician?
Cheers.
Muffster.

Rsmat

iTrader: (2)

danneth put a few plugs on in his time and mess about with car speaker.....

focusv8

How are you getting the power into the van and consumer unit?
And where from, generator or mains?


Length of time to search 15 seconds, don't know what you've been doing wrong;

http://www.diydoctor.org.uk/projects/consumer_unit.htm

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danneth

yes mate i am, add me to msn if you use it

surzz60@msn.com

danneth

cunt

slider

very difficult to explain and i cant find a decent picture or drawing either, best bet is to get someone to have a quick butchers at it, feel free to email me a pic and ill tell you if its ok

Rsmat

iTrader: (2)

fuckinghell next thing ull be going round to see his puppys...

be carefull......

jerh20

Hi
if its the wiring to the socket ur worried about then it should be 2.5 sqmm 'twin and earth' cable, controlled by a 20 amp RCBO or MCB/RCD. Sockets are generally on 20A MCB/RCD or RCBO and lighting is generally controlled by 10A MCB only. Heres a diagram that might be use to u. And a handy tip to remember is that an mcb or rcbo is there ONLY to protect the cable and not any appliances(thats what the fuse in the plug top or fuse in flouresent lights for example is for)

http://www.aboutelectricity.co.uk/im...l_circuits.JPG

muffster

Thanks for the replies fellas.


Yes mate i have seen this page before. The description on it is not that clear, it doesnt show how the MCB is connected to the main switch.

Some more info: Its for a 230v hook-up just as per any caravan site. 230v is supplied to the van via a lead with sausage plug connection going to a waterproof socket under the van. All i need it to supply inside is normal domestic light, laptop etc. Nothing fancy or anything which draws a large load.
Thanks,
Muffster.

focusv8

Incoming from inlet connector outside of van goes into top of main switch / main rcbo.
Copper bussbar goes from LIVE at the bottom of main switch to bottoms of MCBs.
Neutral from bottom of mainswitch goes to common bar on the side of the unit.

Cables to circuits go;
Live from top of Mcb,
Neutral from common Neutral bar
and Earth from common earth bar.

Better pic?
http://www.ultimatehandyman.co.uk/co...split_load.htm

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jerh20

Spot on as above but make sure that the socket circuits go to the MCB's controlled through the RCD

muffster

Great,thanks for that fellas, i will check that against my consumer unit at the weekend.

jerh20, can you explain a little further was you meant by this: 'Spot on as above but make sure that the socket circuits go to the MCB's controlled through the RCD'

Many thanks,
Muffster.

focusv8

That applies if you are using a split load consumer unit which I doubt you are.
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StephenC

eh?? you sure you worte that right? just about every bit of that goes against anything Ive ever been taught.

snoopaloopa

iTrader: (3)

+1

StephenC

jerh20, clue for you, why do you think the RCB has a milliamp rating??? surely a cable can handle more than that????

rstdave

iTrader: (3)

+2, but i think it's just how it's worded as i can tell what he's getting at..... on a 32A ring circuit for example, the mcb is protecting the cable from carrying more than 32A, and as the circuit is suppling 13A socket outlets whatever is plugged into that circuit has to be covered by a lower rated plugtop fuse.
However as the mcb's are more sensitive than the plugtop fuses they often operated before the plugtop fuse anyhow therefore offering some protection to the apliance.....and in the case of a lighting circuit the mcb's certainly offer protection, and an RCD is a totally different thing altogether detecting earth faults that no plugtop fuse will detect anyway

jerh20

focusv8 provided a link with a photo which is a split load unit, that is lighting to the left(not RCD controlled) and sockets to the right(RCD controlled). my point was NOT to put the sockets through the MCB's on the left as they wouldn't have RCD protection. Stephenc, of course the cable can handle more than the milliamp rating, its the main current carrying capacity its rated for eg.10A 20A etc. the milliamp rating, usually 30mA, is the amount of earth leakage current allowed b4 tripping of the device. Any higher earth leakage could be fatal. RCD's dont have any overload or short circuit protection, only earth leakage protection. RCBO's have all 3. Any RCBO or MCB is there to protect the cable, not any appliance connected down the line. What good would a 20A MCB, for example, be at protecting something that can only handle an amp or 2 of current without burning out. Like take a playstation or something takes what 150w? if something happens in it and it takes more juice than normal its the fuse that'll blow for protection to the unit. yes if theres a major fault obvisouly the MCB will go and protect it that way, but the fuse in the unit is suppose to protect that individual appliance.

StephenC

jerh20, my main point was that "rcbo is there ONLY to protect the cable", isnt strictly true, its there to protect YOU. Your right with what your saying regarding fuses protecting devices but every part of the installation protects downstream devices in case certain parts fail, i.e. the mcb will step in if the fuse fails and your main incoming breaker will eventuallly step in should your socket MCB fail for whatever reason. Wasnt having a go or doubting your knowledge but in an installation like this ,i.e. a campervan, I think human safety is paramount compared to the cable in the van.

jerh20

stephenc your right, sorry i misinterpreted ur post. human protection is first and formost of course, my point is just that MCB's and RCBO's are not there to strictly protect connected devices down the line. of course certain problems arise and then they do protect the devices.i.e short circuits etc. I should have made that clearer in my original post.

muffster

Lots of good info on this from those in the know, thanks for that.

[QUOTE=focusv8;4810047]Incoming from inlet connector outside of van goes into top of main switch / main rcbo.
Copper bussbar goes from LIVE at the bottom of main switch to bottoms of MCBs.
Neutral from bottom of mainswitch goes to common bar on the side of the unit.

Cables to circuits go;
Live from top of Mcb,
Neutral from common Neutral bar
and Earth from common earth bar.

Better pic?
http://www.ultimatehandyman.co.uk/co...split_load.htm

I followed this description from jerh20 and that is just how i had wired it in, always good to check though! cheers mate.
So in my mini consumer unit ive got a main switch and two MCB's which have BS 32 and BS 6 on them, im assuming they are 32 and 6 amp MCB's then? (feel free to take the piss)
What size MCB do i need to power a double socket in my campervan which will be used for normal domestic appliances, 13a?
It has a standard 35mm DIN rail in it so would any other make/manufacturer of MCB just simpley slot in?

Many thanks.
Muffster.

jerh20

Muffster, assuming the cable is 2.5mmsq then no larger than 20A. I;m guessing that BS32 refers to British Standard 32A. 99% sure thats the case. Does it say just B32A,C32A or D32A anywhere on the MCB? What make r they? Can u put up a pic?

muffster

Ok mate i will have a look at the unit closer today. Will try to put some pics up but i an chuffing useless with computers!!!!!

Cheers,
Muffster.

(on a more positive note i put my RWD cos in for MOT yesterday, only done 600 miles since last test and not been used for 6 months. It passed,no advisery's. Phew!)

muffster

Hello mate here are a couple of links to some pictures, hopefully they will work!
Cheers,
Muffster.


http://i969.photobucket.com/albums/a...merunit064.jpg
http://i969.photobucket.com/albums/a...merunit062.jpg

St3V3_C

Is that flex you've wired it up with? LOL.

It will be fine - should be a smaller breaker for the sockets - 16A - but as the caravan site sockets will only ever be a maximum of 16A you will be fine.

Toolstation (I think) sell CTI stuff, but there are only 2 or 3 physical sizes, so some other makes will fit. It's the hole at the bottom that needs to be in the same place, but differs on some makes.

muffster

Yes! the orange cable is the same stuff used with the 230v hook up cable, i just cut a piece of as i didnt have any twin & earth. I used another short length to go to a twin socket.
So can you tell from the pics what size MCB's they are, and is the 63A, 30MA RCD acceptable? (i said earlier i had a main switch not an RCB)
Cheers pal,
Muffster.

teamfatboy

However as the mcb's are more sensitive than the plugtop fuses they often operated before the plugtop fuse anyhow therefore offering some protection to the apliance..



Rubbish BS1361 fuses are fare more advanced than an MCB. The reason that they are not used is due to the fact you need tools to replace them and is so not convenient to end users

cosy trav

iTrader: (1)

You can get BS1361 fuse carriers for household consumer units . There a pain in the back side if the lights blow due to you needing to find a 5amp fuse in the dark LOL .

There not used alot on house hold installs in consumer units because of the convenience to the house holder . Its easier to flick a switch than find and change a fuse . BS 88 fuses are the safest current breaking devices too use .

jerh20

muffster, looks fine except it seems u've got the neutral from the hook up lead going into the main neutral busbar. u need to connect that into the neutral connection on top of the RCD otherwise the rcd will trip out straight away, or at least when u plug something into ur 13A socket. i'd still change out that 32A(yes they are 32A and 6A respectively)for a 16A or 20A MCB just in case. I know that the 'hook up' socket is 16A, Prob backed up with a 16A or 20A breaker, but if the socket is overloaded then its the breaker for the 16A socket that'll prob go b4 ur own 32A. 63A 30ma rcd is fine to use. Flex isnt ideal but should do the trick!!!!

muffster

Yes i did cheat and use the 230v hook up cable!
I will change the neutral connection and put it into the MCB and get some lower ampage MCB's.
Thanks for reading and thanks to jerh20 for your input, top man.

Cheers,
Muffster.

jerh20

I hope u meant 'I will change the neutral connection and put it into the RCD' not MCB!!!!!!! Nice big bang otherwise!!!!!!!!! No prob mate, happy caravaning!!!!

muffster

ha just checking you were still awake!!!!!!!!!
Cheers,
Muffster.