Parallel Conductors.

[Rampage]

Going slightly off piste on my D&V Project again.
I'm thinking of running parallel conductors for an electric gate supply 'just to learn about it'.

After reading the BGB it seems quite simple, in that the sum of two smaller cables will be the Iz of the circuit as long as the cables are roughly the same length, material, type, CSA and no branches or separate isolators!
Also, the In can be rated according to the current carrying capacity of both cables as long as they are protected against mechanical damage. Or, separate MCB's can be used for each conductor.


Is it really that simple?

The supply it's feeding is an electric gate, so I guess the thermal constraints could be worked out based on the gate only using power for 30 seconds(?) at a time so that a single cable would survive if the worst came to the worst.

Assuming you used twin and earth(!) for this. Would you run both Lines in one cable and the neutrals in the other, or not, or wouldn't it matter?

Many thanks.
Chris

 

[Rampage]

Yes, I agree, but what does the regulation refer to then? Something like a 3-phase isolator where there are two mechanically linked but not electrically linked MCB's?

 

[Knobhead]

Separate protection can not be used for each cable. ( Well it can, but do you really want to go in to differential protection relays)
L & N must be shared equally between the various cables.

I’d consider it if I needed 50m of 6mm which would have to be ordered and paid for, but in the store room I had 100m of 2.5mm just getting in the way. I actually did this when I got wind that the company was doing a inventory of sub stores and I wanted to loose 100m of 2.5 SWA, it was either that or get my ares kicked for over stocking (I buggered up ordering for another job and had to hide it).