what size cable

[paddypower]

Another novice with a few questions, I’ve searched without coming up with the answers. I’m doing some alterations and wish to do the ground work before getting an electrician to complete the connections.
1. What size cable to install from the meter to the 100A CU with approx 30 foot run? Is it 10mm?
2. What size/type of cable for an underground run between meter and a garage 80A CU with approx 100 foot run ? Do I need armoured or ordinary PVC in plastic conduit?
3. I want the original house CU moving by 6 feet but there is no slack in the cables, how will an electrician bridge the gap? Will it be a case of 10 junction boxes to join the extra 6 foot of numerous cables?

Regards, derek

 

[andy]

1. normal tails are 25mm, not 10mm. for that distance you'll need at least 35mm

2 must be SWA. normal cable wont last long and won have any protection. 16mm cable for this one. the voltage drop will be 2.9% (6.7V)

3why do you need to move it? to extend the cables they can be crimped altho the larger cables (cooker etc) will need to just JB's

 

[ban-all-sheds]

Another novice with a few questions, I’ve searched without coming up with the answers. I’m doing some alterations and wish to do the ground work before getting an electrician to complete the connections.
1. What size cable to install from the meter to the 100A CU with approx 30 foot run? Is it 10mm?

Never in a million years. 25mm² absolute minimum, but almost certainly 35mm².

And it won't be T/E - you'll need tails in conduit, or SWA or split-concentric.

Finally you'll need a 100A switchfuse after the meter.

2. What size/type of cable for an underground run between meter and a garage 80A CU with approx 100 foot run ? Do I need armoured or ordinary PVC in plastic conduit?

Again you must use SWA etc with a local switchfuse at the meter. Size will depend on the load. If it really is 80A over 100' then it'll need to be pretty big - someone with a full set of tables to hand can tell you.

3. I want the original house CU moving by 6 feet but there is no slack in the cables, how will an electrician bridge the gap? Will it be a case of 10 junction boxes to join the extra 6 foot of numerous cables?

He'll probably use crimps.

Re the cables - you should probably confine yourself to preparing the routes, and let your electrician do the specifying.

 

[andy]

Again you must use SWA etc with a local switchfuse at the meter. Size will depend on the load. If it really is 80A over 100' then it'll need to be pretty big - someone with a full set of tables to hand can tell you.

according to the calculator on TLC is should be 16mm

 

[brown-nought]

You mentioned moving the old Cu 6' - do I take it that the 100' and 30' away CU are for supplying garages and sheds??

What matters is not the rating of the CU (I.e. the maximum load they are designed to take) but the real load you are going to run on them. If the garage is never going to run more than a double socket and strip light for example 35, 25 and even 16mm would be a costly over specification.

However, non of this will change the size of the trenches you need to dig. 450mm+ deep.

I'd call the sparky in to advise you - if nothing else he will be please to see you are the one digging out about 7 tonnes of soil!

 

[securespark]

1. normal tails are 25mm, not 10mm. for that distance you'll need at least 35mm

You cannot use tails between a meter and CU greater than a few metres (depends on REC). Any longer run and you need cable.

 

[ban-all-sheds]

You cannot use tails between a meter and CU greater than a few metres (depends on REC). Any longer run and you need cable.

Don't call them tails, then, call them 6181Y singles....

 

[delmel]

Another novice with a few questions, I’ve searched without coming up with the answers. I’m doing some alterations and wish to do the ground work before getting an electrician to complete the connections.
1. What size cable to install from the meter to the 100A CU with approx 30 foot run? Is it 10mm?
2. What size/type of cable for an underground run between meter and a garage 80A CU with approx 100 foot run ? Do I need armoured or ordinary PVC in plastic conduit?
3. I want the original house CU moving by 6 feet but there is no slack in the cables, how will an electrician bridge the gap? Will it be a case of 10 junction boxes to join the extra 6 foot of numerous cables?

Regards, derek

Shouldnt be that far away from the meter, there is a reg for max distance but cant remember. I think it ms something like 3 mts

 

[plugwash]

there is no wiring reg on the length of tails

some elecricity suppliers do place limits on them though which are often in the order of 3M

beyond that they want you to put your own switchfuse at the start

why can't you have the CU near the meter?

 

[ill_wind]

Commercial premises have dis boards remote from the main incomer wired in swa, I think that is the way you will be going.