Single Core SWA

[pope]

I have been asked to install a isolator to extend some cables feeding a chiller.

Normally I would just run another multicore swa to the new location but they have had it designed with 240mm armoured single core to the new location. Of which they are not budging on.

But the chiller is outside so what options do I have for retaining ip rating of the enclosure and stopping eddy currents.

I have a few options I have thought of just seeing how others would do it.

 

[shanky887614]

I have been asked to install a isolator to extend some cables feeding a chiller.

Normally I would just run another multicore swa to the new location but they have had it designed with 240mm armoured single core to the new location. Of which they are not budging on.

But the chiller is outside so what options do I have for retaining ip rating of the enclosure and stopping eddy currents.

I have a few options I have thought of just seeing how others would do it.

would a mf joint be acceptable to extend it?

when i was in derby hospital they have about 4 on tray or in subs that have been extended.

i dont know what size they are but they were thicker than my calfs

 

[pope]

They want an isolator didn't have one before but gives local isolation which is better than not having any. It's just the termination into the metal box retaining the ip rating im after some more ideas on incase someone had a better idea than mine.

 

[shanky887614]

They want an isolator didn't have one before but gives local isolation which is better than not having any. It's just the termination into the metal box retaining the ip rating im after some more ideas on incase someone had a better idea than mine.

jigsaw it out and use a non ferous gland plate if you are going to have multiple swa cables glanded into it.

my engineer stepdad just chirped up they use fr4 plastic for the glandplates

 

[davesparks]

Cut slots between the holes and fill with epoxy

 

[shanky887614]

Cut slots between the holes and fill with epoxy

ive just googled fr4 and apparently its an epoxy sheet, sounds like not a bad material to use.

 

[Besoeker]

I have been asked to install a isolator to extend some cables feeding a chiller.

Normally I would just run another multicore swa to the new location but they have had it designed with 240mm armoured single core to the new location. Of which they are not budging on.

But the chiller is outside so what options do I have for retaining ip rating of the enclosure and stopping eddy currents.

I have a few options I have thought of just seeing how others would do it.

Didn't know you could get single core SWA. You'd think there can't be many uses for it.

 

[Darkwood]

Didn't know you could get single core SWA. You'd think there can't be many uses for it.

If you have ever tried terminating 240mm 4core you will understand why we have SWA singles

 

[pope]

A lot easier to work with four single 240mm2 armoured cables than it is one four core 240mm2.

Darkwood got in there first.

The cutting slots was my first thought with epoxy but sounds a bit rough? Normally I'd make a gland plate but not really enough room to cut the old one out and fabricate something to fit.

 

[shanky887614]

Didn't know you could get single core SWA. You'd think there can't be many uses for it.

i would love to see you try terminating a 500mm 4c ali swa cable lol


they make it as single cores to make it a lot easier to work with

 

[davesparks]

Didn't know you could get single core SWA. You'd think there can't be many uses for it.

Of course you can, it just has aluminium armour instead of steel for obvious reasons.
The use of single core steel SWA is not permitted under 7671.

Confusion comes in due to the two definitions for SWA. It's either steel wire armour or single wire armour.

 

[Besoeker]

i would love to see you try terminating a 500mm 4c ali swa cable lol


they make it as single cores to make it a lot easier to work with

I'd parallel a number of smaller 3/4 core cables. Removes potential eddy current problems and easier to work with.

 

[davesparks]

I'd parallel a number of smaller 3/4 core cables. Removes potential eddy current problems and easier to work with.

Far too sensible, it'll never catch on!

 

[Besoeker]

I have been asked to install a isolator to extend some cables feeding a chiller.

Normally I would just run another multicore swa to the new location but they have had it designed with 240mm armoured single core to the new location. Of which they are not budging on.

But the chiller is outside so what options do I have for retaining ip rating of the enclosure and stopping eddy currents.

I have a few options I have thought of just seeing how others would do it.

Check tables 4D3A and 4E3A of BS7671.
Particularly the note about the armour.

 

[pope]

Regs book is in office in London. I'll check it first thing tomorrow.

 

[shanky887614]

Check tables 4D3A and 4E3A of BS7671.
Particularly the note about the armour.

i thought single core was in the regs books? ill have a quick look

edit:

page 360 byb

 

[Besoeker]

Regs book is in office in London. I'll check it first thing tomorrow.

Non-magnetic armour.

 

[Deleted member 26818]

If AWA is used, it is usual to also use Alimnium glands.

 

[davesparks]

If AWA is used, it is usual to also use Alimnium glands.

Usual? Don't you mean necessary?

 

[Deleted member 26818]

No, I mean usual.