Dan delaMare-Lyon wrote:


One question tho - why oh why oh why are the circut joint boxes such a
pain in the arse to work with? What's wrong with a "busbar" type join
box? Surely these things must exist?

God put us on this earth to suffer; it affords Him a little harmless
pleasure to watch us lose the stupid little headless
screw/slotted-thread thing while we wire up those nasty little JBs
overhead. He often arranges for his minor henchman Sod or his stand-in
Murphy to arrange for said screw to bounce/roll somewhere non-obvious,
so that we raid the next JB for a spare; and if torturing of mortals is
particularly on the agenda for the week, He'll arrange for the screw to
be standing sharp-unfinished-edge-up next time we're walking past with
bare feet.

As to "why not busbar style" - fractionally higher material cost, I
guess. Ceiling roses are "busbar" style, but don't allow multiple cable
entries in as pleasing a style as conventional JBs. A 10-pack of
clip-on-lid, stepped-size-rubber-pseudo-gland square Sarel boxes can be
yours at RS for a mere 8.63quid+VAT with no terminal blocks (251-5633),
in which you can wire with nice commoning blocks such as the ones made
by Zeta (with a rising clamp rather than the cruder direct-screw-down
style), sold by RS as e.g. partnum 315-4790, 10quid for box of 10 3-way
commoners, or 315-4829, 12.50 for a 10box of 5-ways. They allege to be
Man Enough for up to 60A of sustained load, so won't be the weak point
in your design; you might want to use those for E, N, and maybe perm-L,
while using a way or two of the physically smaller choc-block for
switched-L and maybe perm-L, which you'll have fewer cores of. Pricier
than the "I Can't Believe It's A Junction Box" sort of thing you can get
at 60p a time, of course, but may be worth the improvement to your
sanity. There are DIN-rail mounting variants too, which can be handy in
wiring radial circuits with multiple departure points, or Cunning
Electrickle Projects...

....................................... ISTR seeing this type of
connection used in electro-mechanical systems I've worked on in the
past - what's so wrong about them?

Nothing other than cost ;-)

Cheers, Stefek