RCBO mains board help

[YoungBart]

Hi all, I'm an apprentice and tommorow I've been given the job of installing my first (larger) RCBO filled mains board. I've done one before but that was just 4 ways single phase. This has 11 ways 3 phase (8 showers 6mmt&e, 2 heaters 2.5mmt&e and Lighting circuit 1.5mmt&e). Just wondered if anyone has any tips on making it neat. (Using sqaure D/Schneider RCBO's), As the Neutral and earth wires are coiled up (why?) it can look a bit untidy. Any tips?

 

[trev]

As it's your first no one will be expecting it done in record time, so take as long as you can.
Will you be supervised on this one? If so ask the supervisor gadgie for how he would like to see it

 

[sedgy34]

dont you take note from what the electrician does

 

[YoungBart]

Thanks Trev, and Yes I'll be supervised. Sedgy Yes I do take note of what my colleagues do, I was just seeing if anyone on here had a different way that might make the work look easier. Forgive me but I thought that a forum for electricians might well be a useful place to gain additional electrical knowledge.

 

[trev]

If the circuits are wired in singles a lot of people use cable ties to bunch their cables together and leave a loop before they enter the respective terminations to allow a little slack for future alterations/maintenance

 

[sedgy34]

you are forgiven lol
i would say this!!! do it how you think we all learn from our mistakes that is what makes us better in what we do!!

 

[YoungBart]

We normally leave loops in our board (Neatly of course), And I often neaten them up further with Tie wraps, Does anyone know if this method (tie wrapping in the DB) is a problem, i.e. causing damage to the cables etc?

 

[trev]

As an apprentice (Many years ago) I didn't have the benefit of internets where I could ask questions. All I had was a slightly overweight, balding man who would strike me if I repeated a mistake. While I sometimes lament that I am not allowed to strike some useless disinterested boy, this one should be applauded (imho)for sticking his head into what can sometimes seem like the lions mouth and wanting to do a nice neat job, come the advent of the learning sub forum I hope many more will come along

 

[sparky05084]

I remember when I first did a 3 phase board and I was absolutely cacking it!

Seemed to take me forever to mount the bleedin thing never mind connect the circuits up

As others have said, take your time and pay attention to what your doing. I'm sure you will do a fantastic job. Good luck.

 

[RISElectrical]

Although cable ties make it look neat and tidy it's one of my pet hates! Perfect tidy looking 18 way TP&N, rammed full of neat little cables all ties together... Then you have to rearrange some circuits or move them etc, add a new circuit... All live and you can't get anywhere without cutting off all the ties!

Or try and trace a rouge neutral on a T+E installation and you can't because whenever you tug the line everything in the bloody board also moves as they are all bunched together. Also when doing an EICR it can be a nightmare getting to the N and CPC when everything is bunch together and not connected in sequence.

I remember years ago when we had our NICEIC inspection the asseessor at the time said he didn't like seeing cable ties in boards.

 

[Andy78]

Running the cables behind the busbar assembly can make a neat job and give you room for your rcbos. You can remove this assembly on some makes and this definately makes this way of cabling the board easier.
Sticky pads with cable tie loops can make a neat job, but ask your sparks what he wants to see. Some will frown on you bunching live conductors in a DB.
Are you assigning circuits to a deignated schedule or are you working it out yourself ? If you are, bear in mind load balancing across phases and putting larger loads nearer the incomer.
I'm sure you will do a fine enough job. Take your time, and enjoy the finished result.

 

[trev]

putting larger loads nearer the incomer.

Why? apart from it looking a little tidier there's no benefit/need for this. The busbars are rated at whatever they are along their whole length

 

[trev]

apart from it looking a little tidier

Imho anyway

 

[Andy78]

Force of habit really. Got it beat into me years ago that it was good practice.

 

[mogga]

down the back of the bussbar looks cracking tywraps tend to get frowned on if LEFT by all means use them and leave on otill finished then remove
NUMBER NUMBER NUMBER !!!!! number cables keep sequence IF you can feed the curly neutrals down the back of pan assembly all the better and KEEP to the db schedule you are given

 

[VoltzElectrical]

down the back of the bussbar looks cracking tywraps tend to get frowned on if LEFT by all means use them and leave on otill finished then remove
NUMBER NUMBER NUMBER !!!!! number cables keep sequence IF you can feed the curly neutrals down the back of pan assembly all the better and KEEP to the db schedule you are given

agree. get some decent ferrules.

 

[Guest111]

Whatever you do make sure you get both live legs of the same ring on the same breaker, a spark working with me once put one live on red1 and the other leg on yellow 1 powered up and BANG .You really dont want to go there, better to take 2 hours and get it right first time rather than do it in an hour and have to do it again!

 

[YoungBart]

Are you assigning circuits to a deignated schedule or are you working it out yourself ? If you are, bear in mind load balancing across phases and putting larger loads nearer the incomer.
I'm sure you will do a fine enough job. Take your time, and enjoy the finished result.

I've worked out all the load balancing etc for the job, My 'supervisor' wanted to give me the chance to work my way through a more complex board, So all that has been done.
But thanks for the replys guys, some helpful tips and some good points raised, especially about the tie wraps, I've often wondered how people view that idea.
Thanks again
James

 

[YoungBart]

Whatever you do make sure you get both live legs of the same ring on the same breaker, a spark working with me once put one live on red1 and the other leg on yellow 1 powered up and BANG .You really dont want to go there, better to take 2 hours and get it right first time rather than do it in an hour and have to do it again!

Luckily theres no ring for me to make that mistake THIS TIME. Just 8 showers, Lights and 2 heaters.

 

[J&M Electrical]

As others have said really, just take your time..Number all the conductors so they are easily traceable (This was a requirement on the AM2 when i did it 5 years ago so it will be good practice), Balance your loads (like you have said), and make sure everything is tight. Personally i like using just a couple of cable ties down each side just to keep everything neat and tidy. This also helps keeping terminated cables out of the way whilst your still working on the board. Get some pictures up of it when your done.