volt drop and extended meter tails

[TTbangbang]

I was intending to split and extend my meter tails by 10m in order to have less cable runs through the house and to reduce the volt drop effect.

Is the 10m meter tail length not considered to have any volt drop? ?:| ? :| ?:|

... or should I be adding it to each circuit's volt drop value?

Thank you for any explanations

 

[SPECIAL LOCATION]

525.3 Refers to voltdrop from the origin of the installation, (usually the supply terminals)..

I usually consider it to be where my tails join the meter! ?:|

 

[TTbangbang]

Thank you.

Entry in notebook: There's no point, voltdrop-wise, in extending meter tails.

Job done Guiness Drink

 

[heathelect]

I was intending to split and extend my meter tails by 10m in order to have less cable runs through the house and to reduce the volt drop effect. Is the 10m meter tail length not considered to have any volt drop? ?:| ? :| ?:|

... or should I be adding it to each circuit's volt drop value?

Thank you for any explanations

Dont forget when extending tails over 3m away from meter youll need to protect them with a switch fuse of some sort, daveGuiness Drink

 

[daryl631]

Dont forget when extending tails over 3m away from meter youll need to protect them with a switch fuse of some sort, daveGuiness Drink

yes i had to do job meter 7 metres away from cu used a kmf800 80A fused main switch

 

[cheggers]

and if those tails are embedded in the fabric of the building less than 50mm, rcd is needed.

 

[SLIPSHOD & SLAPDASH]

and if those tails are embedded in the fabric of the building less than 50mm, rcd is needed.

And that is now not allowed as you must have more than one rcd protecting an installation (if of course there is more than one circuit !)

Any sub- main will now have to be either surface, SWA or in steel conduit.

 

[SPECIAL LOCATION]

Thank you.Entry in notebook: There's no point, voltdrop-wise, in extending meter tails.

Job done Guiness Drink

Just as a side point..

assume you were taking your tails 10m away,

The Max demand was 70amps

25mm mv/a/m = (1.75 x 70 x 10) / 1000 = 1.22volts

if only 30amps running

(1.75 x 30 x 10)/1000 = 0.53volts

so you are only going to loose between 0.5 & 1.25 volts down your tails

in this example... probably not a major issue?

 

[TTbangbang]

...Any sub- main will now have to be either surface, SWA or in steel conduit.

Would 16mmsq tails running under floorboards i.e at least 50mm down from the top surface of the floorboard, lying in air except where crossing notched joists have to be SWA'ed or conduit'ed? ?:|

 

[Apache]

Would 16mmsq tails running under floorboards i.e at least 50mm down from the top surface of the floorboard, lying in air except where crossing notched joists have to be SWA'ed or conduit'ed? ?:|

Thought the consensus was use 25mm tails?

There's another thread..............

 

[TTbangbang]

Thought the consensus was use 25mm tails?There's another thread..............

Yes, but my existing tails are 16mmsq with 60A cutout fuse and EDF are in no hurry to upgrade.

Maybe they will when I've finished the rewire... ] ] ]

 

[SPECIAL LOCATION]

Would 16mmsq tails running under floorboards i.e at least 50mm down from the top surface of the floorboard, lying in air except where crossing notched joists have to be SWA'ed or conduit'ed? ?:|

The less than 50mm depth requirement for cables needing RCD or SWA or Conduit... is if when buried in WALL's Not floors! 522.6.6.

Under floors should be >50mm anyway 522.6.5 (i)

are you using 16mm T&E or singles?

 

[TTbangbang]

The less than 50mm depth requirement for cables needing RCD or SWA or Conduit... is if when buried in WALL's Not floors! 522.6.6.Under floors should be >50mm anyway 522.6.5 (i)

are you using 16mm T&E or singles?

Thanks for that SL - I'm going to have to memorise the red book! I will be using 16mmsq singles. What would be your preference and why? And that question to number 3 please!

(I miss Cilla )

 

[SLIPSHOD & SLAPDASH]

For once i did not use the phrase 'should be' and you have found out why i should have .

If the end runs of your cable are surface then your method would be ok. I would run Tw&e with an additonal earth rather than double insulated.