Thought this might interest you guys. Supply is to a 4-way 3-phase board fitted with a 63A 30mA triple pole switch on a TT earth. Located in a unit rented out to various companies who want it. Cable is 4-core 10mm2 SWA and the joint is an IP65 adaptable box, 30A jb and a connector for the neutral.
Joint On A 3-Phase Sub-Main
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Thought this might interest you guys. Supply is to a 4-way 3-phase board fitted with a 63A 30mA triple pole switch on a TT earth. Located in a unit rented out to various companies who want it. Cable is 4-core 10mm2 SWA and the joint is an IP65 adaptable box, 30A jb and a connector for the neutral.
Interesting technique. Are you sure the cable is 10mm csa? Maybe the photo just makes it look smaller...
i hope there was a lid on when you found it...
Doesn't look like 10mm to me !!
more like 6max going by the JB terminals, if that is a 30A JB......
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Agreed - 10mm wouldn`t fit into the terminals of a standard 30A JB.
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Agree, no way would two 10mm's fit a 30A junction box.
Whether it's "okay" or not depends on the OCPD feeding it. >30A then no it's not okay.
Whether it's "okay" or not depends on the OCPD feeding it. >30A then no it's not okay.
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Well it looks like 6mm to me, sorry.
If you look at the size of the earth bolt [nice use of the banjo/plasic box/nut technique] it appears the same size of the cable if not bigger. AND it looks like a galv 6mm gutter bolt [nice]... You have to zoom in a lot,
Looks like too much slack in the terminals to have 2 x 10mm in them..............just saying
If you look at the size of the earth bolt [nice use of the banjo/plasic box/nut technique] it appears the same size of the cable if not bigger. AND it looks like a galv 6mm gutter bolt [nice]... You have to zoom in a lot,
Looks like too much slack in the terminals to have 2 x 10mm in them..............just saying
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Got to agree with the others ^
Looks like 6.0mm SWA to me,, the earth looks to be 10mm and the live conductors look to be smaller than it (from here that is!)
Also, although looking unconventional, the JB might be ok dependant on the sub mains OCPD
Looks like 6.0mm SWA to me,, the earth looks to be 10mm and the live conductors look to be smaller than it (from here that is!)
Also, although looking unconventional, the JB might be ok dependant on the sub mains OCPD
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even allowing for the thinner sheath of XLPE, it still looks too small for 10mm
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If that`s a 10mm cable then Albert`s my Grandad!
( IIRC, that makes paddler a relative, too :slap )
As others have said, depends on the OCPD - but I wouldn`t like it personally!
( IIRC, that makes paddler a relative, too :slap )
As others have said, depends on the OCPD - but I wouldn`t like it personally!
Right then. I have been to site today and have all the info now. It IS 6mm2 (my humble apologies ; ). The source is a distribution board inan adajacent shed around 30m away. Its on a 63A triple pole mcb. Main switch on the board is a 100A 100mA RCD. I haven't altered the joint just labelled it 400V. Its a mash up really. Also its daft why it was ever jointed. The joined length is around 3m and it would have made more sense to have put the fuseboard in a different position to avoid a joint. So its a 63A supply on a 6mm2 4-core SWA serving a 4-way 3-ph board.
:C
:C
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So it fails on an inadequate rated junction box, inadequate rated cable, and in all probability (depending on length) excessive volt drop.
The only solution is rewire with thicker cable (and avoid the junction)
Or, if the load current is low enough, reduce the OCPD of the source.
The only solution is rewire with thicker cable (and avoid the junction)
Or, if the load current is low enough, reduce the OCPD of the source.
Agreeing with PD here 
I agree, too, but it ain't gonna be rewired, thats for sure. I could recommend a swap out of OCPD for a 50A but decision to do it is out of hands. Farmer owns the place. Joke is the biggest circuit on the fuseboard is mine, a 38m long 3-core 16mm2 SWA hooking up a portacabin. At least VD on that wont be an issue.
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