ESB incoming cable moved and new meter put in. What size fuse would be in ESB cut-out

GreySquirrel · 21-10-2011 02:24PM #1

ESB incoming cable moved and new meter put in. What size fuse would be in ESB cut-out?

bassey · 21-10-2011 04:12PM

Just a domestic house? 80 Amp fuse usually

GreySquirrel · 21-10-2011 05:00PM

bassey wrote: »

Just a domestic house? 80 Amp fuse usually

Yup, domestic house. the supply is coming in from the top from overhead cables. Two crews came out to do the job, one ESb, one contractor. I think the contractor did the actual work.

If it is 80 Amp, what size should the meter tails be? Can the tails be singles or must they be T&E.?

Diggerdunne · 21-10-2011 05:53PM

ya run 16 square T&E from the consumer unit to the meter box usually once its not to far from the meter box....not sure on the exact distance in the regs...

GreySquirrel · 21-10-2011 05:59PM

It's about 1 metre maybe 1.5 m

Diggerdunne · 21-10-2011 06:02PM

well then thats fine...

GreySquirrel · 21-10-2011 06:27PM

I have the 4th edition rules, not near me at the moment. It gives two different distances, I think. 3 m and 2 m. I'll check later. The're not the clearest documents I've seen.

M cebee · 21-10-2011 06:48PM

if you use singles it ahould be 16sq pvc earth going by the book

the cut-out doesn't protect tails at all now

GreySquirrel · 21-10-2011 07:58PM

430.4 (I'm paraphrasing now):

Main overcurrent protective device at supply point or within 3m of supply point.

GreySquirrel · 21-10-2011 08:52PM

GreySquirrel wrote: »

I have the 4th edition rules, not near me at the moment. It gives two different distances, I think. 3 m and 2 m. I'll check later. The're not the clearest documents I've seen.

Within 3 metres for main overcurrent protection and 2 metres for main isolation switch (from main supply point)

GreySquirrel · 21-10-2011 10:14PM

M cebee wrote: »

if you use singles it ahould be 16sq pvc earth going by the book

the cut-out doesn't protect tails at all now

yup. For singles the earth has to be same size as live conductors up to 16 square.

says tails need to be for 63 Amp - 16 square; 80 Amp - 25 square

M cebee · 21-10-2011 10:28PM

only up to 16?

GreySquirrel · 21-10-2011 10:50PM

for area of phase conductor less than or equal to 16, area of protective conductor to be equal to area of phase conductor.

16 < area of phase conductor less than or equal 35, protective = 16

GreySquirrel · 21-10-2011 10:55PM

Off to bed, will clarify any questions tomorrow. The rules are quite difficult to read. you have to keep jumping back and forth for references

M cebee · 21-10-2011 10:57PM

ya i read it before but forgot

i don't find them hard to understand-just hard to remember

GreySquirrel · 23-10-2011 01:53PM

Ok. I have two options for routes to run the meter tails: up, over and down - less than 3 metres; down, over and up - more than 3 meters but this is the easier route.

If I go by the Rules for the longer route, greater than 3 m, I'll have to put in a Main Overcurrent Protection Device and then run cable from that to the board.

Also if I go by the Rules, not definitely knowing if the ESB fuse is 80 A or 60A I should run 25 mm squared tails.

Any comments?

M cebee · 23-10-2011 03:02PM

no

you dont size the tails according to cut-out fuse anyway

i would just fit the 63amp main ocpd in cabinet

GreySquirrel · 23-10-2011 04:59PM

okily dokily

GreySquirrel · 25-10-2011 02:18PM

M cebee wrote: »

no

you dont size the tails according to cut-out fuse anyway

i would just fit the 63amp main ocpd in cabinet

I'm going with a Hager switch-fuse 63A. I have T&E 16 mm and also singles 16 mm, including 16 mm PE. Not sure which route to take.

M cebee · 25-10-2011 02:23PM

The main ocpd has to be a mcb
with a high breaking capacity about 10KA

GreySquirrel · 25-10-2011 02:57PM

have 63 A mcb 10kA breaking capacity

GreySquirrel · 25-10-2011 10:05PM

GreySquirrel wrote: »

have 63 A mcb 10kA breaking capacity

Ok, so what did i do? dropped the mcb and an spd through the opening in the suspendded floor

GreySquirrel · 26-10-2011 02:24PM

GreySquirrel wrote: »

Ok, so what did i do? dropped the mcb and an spd through the opening in the suspendded floor

Rescued. Have to wire in the spd next

GreySquirrel · 01-11-2011 06:11PM

The mains is connected to the board through a 63 Amp 10,000 Amp MCB.

Main Surge Protection Device is installed. next is to install the secondary SPD and TV etc circuits.

ESB incoming cable moved and new meter put in. What size fuse would be in ESB cut-out

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