Distribution circuit question

[LlandrilloSpark]

I'm running a 30 metre length of three core 16mm armour to feed a garage conversion which could have a high loading.
The cable will be run from the external meter box where I will split the meter tails via a Henley
The problem is There is naff all room in the box and I can't fit a switched fuse in there to protect the armour as the main cut out is 100A
Can I put the switched fuse of another suitable protection device at the other end to protect against overload?
Cheers

 

[SPARTYKUS]

DPG

I think thats the usual way to do it. As close as poss ( as mentioned within a few metres to keep em quiet)

 

[Guest123]

We're talking two different types of protection here I.e overcurrent & short circuit.

Before we were mainly talking overcurrent protection which ad I said previously can be placed anywhere along the circuit, (433.2.2)

Reliance on the suppliers fuse for short circuit is debateable and IMO in this instance wouldn't be accepted by the DNO should they find out.

Sent from my BlackBerry 9800 using Tapatalk

 

[LlandrilloSpark]

Problem Solved

Got a 100mm x 190mm metal clad enclosure with 80A main switch and 63A MCB, its proteus(CEF) so not the best but it will do the job at origin, im going to have to move the mainswitch slightly in the meter cupboard to fit it in but at its the best i can do

cheers for the input, ive enjoyed reading it all!

 

[Mike Watters]

how will you know if the armour cpc is big enough?

 

[Guest123]

how will you know if the armour cpc is big enough?

He's used a 3c SWA, the armouring is not being used as the CPC due to the 3rd core.

 

[malcolmsanford]

how will you know if the armour cpc is big enough?

View attachment SWA-pvc-xple cpc comparision.pdf

And if he was he may have used the attachment as a guide

 

[Engineer54]

View attachment 10506

And if he was he may have used the attachment as a guide

I never use that table, the one originally posted by Spin in the same ''STICKY THREAD'', is the one to use, and have done for a number of years now. In your link a 16mm SWA cable fails to meet compliance for a XLPE 3 core cable, whereas in the alternative table it DOES comply.... It would also comply in 2 core 16mm form as well!!


Table for 90[SUP]0[/SUP]C Thermosetting SWA cables operating at 70[SUP]0[/SUP]C.

Conductor CSA​	Minimum CSA of SWA to meet 54G​	CSA of armour 2 core​	CSA of armour 3 core​	CSA of armour 4 core​
1.5​	3.4​	16​	17​	18​
2.5​	5.7​	17​	19​	20​
4​	9.0​	19​	21​	23​
6​	13.6​	22​	23​	36​
10​	22.6​	26​	39​	43​
16​	36.1​	41​	44​	49​
25​	36.1​	42​	62​	70​
35​	36.1​	62​	70​	80​
50​	56.4​	68​	78​	90​
70​	79.0​	80​	90​	131​
95​	107.2​	113​	128​	147​
120​	135.3​	(125) ​	141​	206​
150​	169.2​	(138​	201​	230​
185​	208.6​	(191) ​	220​	255​
240​	270.6​	(215) ​	(250)​	289​
300​	338.3​	(235) ​	(269)​	(319)​
400​	451.0​	(265) ​	(304)​	(452)​