Terminating SWA in Isolator

[comptonspark]

Have a refurb job at the moment and will end up with an outside meter box and two remote CUs about 5m away, which will be back to back on the same wall with one feeding the main house and the second supplying a new annex. Supply is TNC-S

So my plan is to fit a 100A isolator in the meter box then run a 25mm three core SWA to one of the CUs and then henley block the supply to the second CU through the adjoining wall.

I have a couple of questions on the details, when I terminate the SWA at the isolator in the meter box, do I need to take the earth core to the main earthing terminal (supplied by the DNO) rather than terminating it within the isolator and taking a separate earth cable to the main earth terminal?.

With a 25mm SWA what size gland do I need, I've noticed that the isolator has a 32mm cutout so should I use this?or would a smaller gland in a separate drilled hole be better?

Also I think I need to run a separate 25mm earth to the second CU is this correct ?

thanks - Michael

 

[benji]

think you should use a sw/fuse rather than an isolator

what size is the fuse in the cut/out.

if you gland swa into consumer unit where are you going to put the henly block and how are you wiring it from the cu.

why not fit 2xsw/fuse at the meter box and a seperate swa to each cu.

yours benji

 

[comptonspark]

sorry didn't make myself clear in original post,yes i was planning on using a switch/fuse in the meter box with 100A fuse. At the CU I would plan to terminate the SWA in a separate box then into henley and then into CU. However I think your 2 x SWA idea is better, but perhaps more costly?. Also i haven't seen a small two way switch fuse that would fit (the Wylex 110 is big enough as it is)!so any suggestions welcome.

 

[batty]

Is supply already there if not DNO may not like you fitting a 110m as it takes up quite a bit of room in there box.

 

[comptonspark]

It is an existing supply, but DNO will be moving meter to the new meter box,hence the need for the long tails,switch/fuse etc.They seemed quite happy about the switchfuse when I talked to them about it,however as you suggest reality on the day might be different- does tea and lots of chocolate biscuits usually do the trick?

 

[batty]

It is an existing supply, but DNO will be moving meter to the new meter box,hence the need for the long tails,switch/fuse etc.They seemed quite happy about the switchfuse when I talked to them about it,however as you suggest reality on the day might be different- does tea and lots of chocolate biscuits usually do the trick?

All depends who dno are EDF tend not to be too helpful, sse always seem to be helpful if they can in my experience.