My 1st board on site advice

[MrShine94]

Hello,

I have just competed my 1st consumer unit install on site. I would like some advice on how I may improve the quality/neatness.

All constructive criticism welcome

Thanks

 

[MrShine94]

Ok so for point B regulations:



The cable tie, is purely my opinion, use them to make it tidy and then I would remove, the cables should have been formed into position.

I don't like it as in older bigger DBs with more circuits, especially ones that have been poorly terminated, it's a pain in the --- trying to trace a wire when they're cable tied.

Other people will argue it's not a good idea, as you're bunching conductors together and could potentially cause a hot spot.

Thanks for the reply. I had a read over that regulation you supplied but can’t see how it applies to the neutral fly leads. I would rather not have to go back and install Ferrules. Time consuming. I will if it’s a legal requirement.

 

[Bobster]

Thanks for the reply. I had a read over that regulation you supplied but can’t see how it applies to the neutral fly leads. I would rather not have to go back and install Ferrules. Time consuming. I will if it’s a legal requirement.

They are fine stranded conductors... (fine wire)

526.9.1 In order to avoid inappropriate separation or spreading of individual wires of multiwire, fine wire or very fine wire conductors, suitable terminals shall be used or the conductor ends shall be suitably treated.

Those terminals in the CU are not spring loaded, so the conductor must be suitably treated. E.g ferruled.

From the factory you will likely notice that the ends before you cut them are ultrasonically welded.

 

[MrShine94]

Ok so for point B regulations:



The cable tie, is purely my opinion, use them to make it tidy and then I would remove, the cables should have been formed into position.

I don't like it as in older bigger DBs with more circuits, especially ones that have been poorly terminated, it's a pain in the --- trying to trace a wire when they're cable tied.

Other people will argue it's not a good idea, as you're bunching conductors together and could potentially cause a hot spot.

Thanks for the reply. I had a read over that regulation you supplied but can’t see how it applies to the neutral fly leads. I would rather not have to go back and install Ferrules. Time consuming. I will if it’s a legal requirement.

They are fine stranded conductors... (fine wire)

526.9.1 In order to avoid inappropriate separation or spreading of individual wires of multiwire, fine wire or very fine wire conductors, suitable terminals shall be used or the conductor ends shall be suitably treated.

Those terminals in the CU are not spring loaded, so the conductor must be suitably treated. E.g ferruled.

From the factory you will likely notice that the ends before you cut them are ultrasonically welded.

Thanks a lot been a great help

 

[davesparks]

Thanks for the reply. I had a read over that regulation you supplied but can’t see how it applies to the neutral fly leads. I would rather not have to go back and install Ferrules. Time consuming. I will if it’s a legal requirement.

If you don't fit ferrules some of the strands will not make proper contact in the terminal as they are pushed out sideways by the screw.
This leads to overheating and you will be back to replace the higher rated/loaded RCBOs because that connection has failed.

 

[Bobster]

If you don't fit ferrules some of the strands will not make proper contact in the terminal as they are pushed out sideways by the screw.
This leads to overheating and you will be back to replace the higher rated/loaded RCBOs because that connection has failed.

Also copper creep.

This is more prevalent on larger cables than these, but it does still happen.

 

[Dustydazzler]

FOR A FIRST ATTEMPT IT LOOKS VERY NEAT INDEED.

I have worked with sparks in the trade for over 25 years who's boards are not nearly that neat.

 

[westward10]

Depends if you have actually cut the fly leads if not the factory ends should be okay. I cut and ferruled these.

 

[FatAlan]

Di

My point about ferrules is a must, you're contravening BS7671 not doing. My other points are merely my opinion.

Did query that on my Elecsa assessment as I’d shortened some of the RCBO fly leads and re crimped the ends. Told that if I hadn’t done so it wouldn’t have been compliant.

 

[davesparks]

Top row, there’s a 16A in between 6A.
Personally, I like to have descending sizes from the main switch.
Bottom row needs more blanks if top and bottom are same number of ways.

Speaking of the mainswitch.... there’s no tails connected yet. Post another photo when they are in and we will constructively criticise then.

Where do you get white t&e that looks like Sky shotgun cable?

It's actually technically better to alternate high and low load mcbs so that you don't have all the highest loaded mcbs next to each other as they are the ones which heat up the most in operation.

Draka started doing T&E that looks like shotgun cable a few years ago, personally I don't like it.

 

[Deleted member 26818]

I’ve used some of the shotgun type T&E, and it was a right pain stripping it back.
I also don’t like cable ties in DBs, mainly because of the hassle it creates when trying to trace circuits, though grouping factors is another issue.
Yes fine stranded wires do need protection in screw terminals, ferrules are neater and more robust than twisting and doubling over.

 

[MrShine94]

S

Depends if you have actually cut the fly leads if not the factory ends should be okay. I cut and ferruled these.View attachment 48658

So if I have not cut the fly leads it’s not a requirement for ferrules ?

 

[MrShine94]

I’ve used some of the shotgun type T&E, and it was a right pain stripping it back.
I also don’t like cable ties in DBs, mainly because of the hassle it creates when trying to trace circuits, though grouping factors is another issue.
Yes fine stranded wires do need protection in screw terminals, ferrules are neater and more robust than twisting and doubling over.

LSF cable is the future unfortunately

 

[davesparks]

S

So if I have not cut the fly leads it’s not a requirement for ferrules ?

If you haven't cut them then the ends should already have a ferrule or ultrasonic weld on them from the manufacturer.
If the ends are just loose strands then they will need ferrules.

The requirementa apply to all fine strands, not just RCBO tails.

 

[Dustydazzler]

Do people generally bother shortening the N fly lead or better to leave long and simply dress down the back of the din bar.
Some RCBOs used to come with those curly whirly N leads which I never bothered to cut and shorten

 

[davesparks]

Yes, shorten the fly lead to suit, otherwise you end up with a massive amount of unnecessary blue cable cluttering up the board.