"Jules" wrote in message
news
On Mon, 26 Oct 2009 23:04:48 -0700, terry wrote:
No problem with 'wire nuts' (i.e. wire connectors) since 1956 when I
arrived in North America. tree residences since then two of which we
built and wired ourselves. Like everything else if they are used
properly no problems at all. There are an estimated at least one
hundred or so in this typical all-electric house built in 1970 (some
inside the connection space of baseboard electric heaters) and we have
had no problems with overheating or bad connections on both lighting
circuits (15 amp maximum) or duplex outlets circuits (20 amp). And in
one case with a three wire heavier connection from the main panel to a
secondary (pony) one.
I've had a few in our place that have been bad, but then maybe they were
never fitted properly when first installed - some of the wiring in our
place is very good, but some of it's a bit of a mess :-)
One UK style wiring item do not miss is those fiddly (silly) little
brass screws in so-called 'chocolate blocks' and/or certain lamp
holders' often made of brass, a soft metal! Easy to strip or mar the
small screw head (or drop one!); they require an additional small
'straight blade' screwdriver. Whereas much Canadian wiring can be done
with one #2 Robertson (square) screwdriver and a pair of pliers.
Yeah, I hear ya there. The ones used in "proper" fittings are robust
enough (equivalent in strength to the terminals on US electrical outlets)
but cheap lamps etc. can still have those and they're just nasty.
Ring main circuits while maybe a good idea are either very uncommon or
not used at all.
Seems so. Although it is more hassle to set up, and I'm never quite
convinced of the loading benefits given that the ring could fail yet still
appear to work; at least with a radial system if a connection goes bad
it's pretty obvious that it's done so.
(http://en.wikipedia.org/wiki/Ring_circuit for the curious)
That was VERY inneresting!!!
Am I correct in observing that the diagram shows two "radial" connections to
the ring?
It took me a while to grok the "point" of the schematic, and when I did, it
left me with a very big Q:
How does a ring circuit SAVE copper? ?
Yeah, I can see how you can use thinner gauge wire, but now you have to use
twice as much of it!
Current capacity (density) is directly proportional to cross-sectional
area, so it seems to me this system is 6 of one, half a dozen of the other,
mass-wise in copper.
The article pointed out some potent disadvantages, as well -- somewhat
dicey, eh?
Interestingly, NYC still has DC running to some older commercial buildings!
And, NYC's 3 phase is 208, not 220 or 240 V, like most of the rest of the
country -- 208 is EXACTLY the rms voltage difference between two 120 V sine
waves 120 deg out of phase, making it, I think, the "purest" type of 3
phase.
Just across any city line, and yer up to 240 -- which bleeve me wreaks a lot
of havoc, machine-wise.
But, I thought Europe was all 220, ie, two hot legs, residentially??
I think 220-240V is a **much better** system than single hot leg 120, as it
is *inherently* balanced, and you don't have to worry about neutrals and
grounds as much -- precisely because of this balance. AND, with lower I^2R
losses, esp. when you consider that many grounds are really crappy, often
using steel cables instead of copper.
g-dAmerica never quite gets it right, unless it comes to fleecing their
public. Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the Media as a condom??
Altho amazingly our vitamins are a lot more available, fwiu. Whazzup wit
dat, over there???
--
EA
Having got used to it rather like the 115 - 0 - 115 volt single phase
domestic service. Although if/when encounters a 3 kilowatt electric
kettle it is till abit of a surprise how quilckly it boils. But how much
boiling water does one need to make one pot of tea anyway! Including
'heating the pot'!
:-) Not having 240V everywhere is one of those things that's taking some
getting used to for me. Plus I've got various 240V things I want to ship
over sometime, and it's going to be interesting planning all the
necessary wiring (most of it's stuff that can live in the 'shop or
basement, so thankfully I don't need to completely rewire the house or
anything!)
Also and not as one would suspect aerial service of both 13KV primary
lines and secondary 115/230 volt wires from pole mounted transformers to
homes results in very fast restore times. Our local utility company line
crews are excellent. Seen them change out a transformer in the middle of
a snow storm, at night, in a couple of hours from the time the 'Power
has gone off" telephone call had been made.
I've not seen much of that here (yet) but I've certainly been impressed
with how few power cuts & brownouts we've had - everywhere else I've
been in the world cuts have been quite frequent and could easily last
a few hours.
cheers
Jules