Meter Tails

[JamesBrownLive]

Just wondered what the general concensus was regarding what seems to be the norm of stripping back a little of the outer sheath of meter tails to show the underlying insulation colour?

Is this acceptable or considered bad practice?

Cheers

 

[Dunc]

Inside the consumer unit i always prefer to strip back a good 2-3 inches of the outer insulation to show which conductor is which. However, no part of the inner insulation should ever be exposed outside of an enclosure IMO.

 

[JamesBrownLive]

Inside the consumer unit i always prefer to strip back a good 2-3 inches of the outer insulation to show which conductor is which. However, no part of the inner insulation should ever be exposed outside of an enclosure IMO.

Have seen quite a few installs where this has happened where the tails go in and out of the meter.
I am planning on installing an isolator between the meter and CU and was wondering if this was something I should avoid doing? I was only thinking of about 5mm, nothing more :shocked3:

 

[Dunc]

Have seen quite a few installs where this has happened where the tails go in and out of the meter.
I am planning on installing an isolator between the meter and CU and was wondering if this was something I should avoid doing? I was only thinking of about 5mm, nothing more :shocked3:

On the meter side of things, if you are using 25mm tails i tend to find that once you've stripped back about 25mm of bare copper you have to strip back another 5-10mm of the outer (grey) insulation to get the cable fully through the hole in the base of the meter. So long as the inner insulation isn't actually visible when you look at the base of the meter then it's fine.

 

[Plonker 3]

Why not just identify the cables by using insulation tape on the outside so tails remain double insulated.

 

[daver]

I was pulled on a recent inspection about this. I had about 2mm showing. His words where. "Why is it double insulated"

Just use insulation tape.

 

[JamesBrownLive]

Ok, thanks for all the replies. Obviously, as it is not considered either acceptable or good practice, insulation tape is the way to go.

Can I just ask one final question re the isolator...

Does it matter (regs wise) if the feed from the meter goes in the top or the bottom of the isolator? I have not decided on its position as yet, but if for example it is only considered acceptable that the feed enters a particluar way, then that will have a bearing on its placement.

Cheers

 

[SW1970]

The usual isolator provided by the DNO has a company side and a user side so you can only enter one way, unless you were mounting it upside down; which would then require very clear labelling as to which switch position was on and off. On the previous question, I use coloured cable ties to indicate polarity. My DNO does this too.

 

[JamesBrownLive]

The usual isolator provided by the DNO has a company side and a user side so you can only enter one way, unless you were mounting it upside down; which would then require very clear labelling as to which switch position was on and off. On the previous question, I use coloured cable ties to indicate polarity. My DNO does this too.

It's not a DNO supplied one as my DNO won't come and install one, they'll only come and pull the bullet.

I'm installing one prior to a CU change and am using one of these:

Wylex 100A DP Mains Switch & Enclosure by Wylex

Does anyone know of any reg that says I must always have the feed side at the bottom, for example? Or am I free to install as I see fit?

Cheers

 

[SW1970]

Thats the same one my dno installs. You have to put tails in at the bottom end unless you're mounting it upside down.

 

[SW1970]

One reg to look at (from amendment 1; haven't got red to hand):

537.2.2.3 ...installed so as to prevent...unintentional or inadvertent closure.

Down is normally off in a domestic setting, hence my point about clear labelling if it was mounted upside down. I'd mount it the right way up.

 

[olly w]

Install it to the manufacturers instructions, if they say it can be wired either way then it can be, if not then it can't be, I personally would not put it in upside down.

 

[colshaws]

I have just opened the box and read the Wylex instructions for one of these isolators and it says "the large cover to be fitted over incoming tails" but as this cover can go either way up I can see no reason why the tails cant go in either way.

 

[platty1005]

It is a generally accepted good practice if not marked up that the feed goes in the top and tails out the bottom as with domestic consumer unit main switch
Upside down is BAD practice it can lead to confusion RE: on/off
Right way up feed in the top tails out the bottom is the way to go

 

[SW1970]

Hi, here's a photo of one of my installations with a DNO installed isolator. Clearly the meter tails go in the bottom and feeds to the consumer unit come out of the top. If an electrician wishes to work on the consumer unit feeds, they can operate the isolation switch, take of the small top cover and remove the cables without interfering with the DNO side of the equipment. Looking closely, the switch is marked as being in the on position.