2 ring finals on one RCBO
- Thread starter SUNRAY
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of course
but you mustn't see it
it's like the Ex-list
a list of things that aren't on lists.
Oh no the whole area is no more than 6 x 10m.
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I read on FB today that in Canada/Aus there should be no more than 1 wire per terminal.
So they don't do rings then.
It all depends upon what the manufacturer of the device specify, some say 2 per terminal - Allen Bradley gear has 2 terminals for each side so allows 4.
So they don't do rings then.
It all depends upon what the manufacturer of the device specify, some say 2 per terminal - Allen Bradley gear has 2 terminals for each side so allows 4.
I suspect that the first inclination of many/most of us is to have similar feelings, but I don't think it's necessarily all that (electrically) rational.
Other than for the question of how many conductors can be satisfactorily terminated in an MCB/RCBO terminal (probably appreciably more than in most terminals of accessories), there's not really anything special or 'magic' about the origin of a circuit. If one short cable ran from the MCB/RCBO and then split into several branches, I don't think many people would call that "several radial circuits"(rather than just "one radial circuit") - and it's not really any different (electrically) if 'the point of splitting' is at the OPD.
The main 'risk' of having, say, two ring final (sockets) circuits protected by the same OPD which a designer needs to consider is that, with many sockets supplied from one OPD, it might "be likely" that the capacity of the circuit (In of OPD) would be exceeded, which is a situation the designer is meant to try to avoid. However, that's not anything to do with there being two ring circuits - exactly the same would be true if all the sockets (the total number on the two rings) were on one, much bigger, ring.
Kind Regards, John
If that is true and if it applies to sockets as well as OPDs, then they couldn't even have radial circuits, unless they have different sockets from ours (but see ** below), with more than one set of terminals. With UK-style sockets, each and every socket would have to be on a 'dedicated' circuit of its own!I read on FB today that in Canada/Aus there should be no more than 1 wire per terminal. So they don't do rings then.
** once upon a time, we had animals like this in the UK, but it's very many years since I saw one for sale (and even those would not facilitate "1 conductor per terminal" in a ring with spurs or a radial with branches - I never saw one with groups of three terminals) ...
Kind Regards, John
They are, but if you mean the US, then I don't think that either Canada or Australia are in that country
In any event, whilst the US (and quite probably Canadian and Australian) ones are 'totally different', it was presumably apparent that I was talking about just one aspect of the design - namely whether they have one, two or more terminals for each of L, N and E - and I don't know the answer to that for any country other than the UK.
Kind Rewgards, John
I should have qualified that with "... until the new-fangled ones with Wago, or Wago-like' terminals recently appeared - but I think they they also only have 'pairs' (not 'triplets') of terminals.
Kind Regards, John
OK - but what's the answer to my question (for any or all of those countries) about the number of terminals?
Kind Regards, John
A regular north american duplex receptacle has two screws terminals (of the style where the wire goes under the head of the screw) each for hot and neutral, i'm not sure about grounds. As the receptacle is shipped the top and bottom outlets are joined together, but tabs can be broken to seperate them (in which case you only get one screw for each outlet).
There are some fancier recepticles that use a different terminal style and can accomodate two wires per terminal (so a total of 4 hots and 4 neutrals on a duplex recepticle).
I think lightswitches generally only have one terminal per pole.
If more wires are needed than there are terminals, the americans use wirenuts to splice the wires.
There are some fancier recepticles that use a different terminal style and can accomodate two wires per terminal (so a total of 4 hots and 4 neutrals on a duplex recepticle).
I think lightswitches generally only have one terminal per pole.
If more wires are needed than there are terminals, the americans use wirenuts to splice the wires.
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We did some work in London for an American company. The consultant came over from head office USA as did a fairly consignment of kit for us to install.
First off they had specified 1 gang and 2 gang backboxes which we had installed, of course at the time we didn't know they had expected US style backboxes, however the standard of the accessories supplied was horrendous. as an example the window blind centre off switches had 6 wrap round screw terminals but the shape of the screw head and the tinned plate forced the wire away from the thread and wires repeatedly came off when fitted to the backbox, the consultant seemed to think this was normal. We had no choice but to fit crimped ring terminals on 1mm² T&E.
The switches themselves felt very hit and miss which explained the reason there were more supplied than required.
The quality of loads of their flexes made the Chinese crap look positively beautiful.
I know we tend to complain about some of our electrical accessories but my limited experience of North American kit makes me realise ours is not bad.
First off they had specified 1 gang and 2 gang backboxes which we had installed, of course at the time we didn't know they had expected US style backboxes, however the standard of the accessories supplied was horrendous. as an example the window blind centre off switches had 6 wrap round screw terminals but the shape of the screw head and the tinned plate forced the wire away from the thread and wires repeatedly came off when fitted to the backbox, the consultant seemed to think this was normal. We had no choice but to fit crimped ring terminals on 1mm² T&E.
The switches themselves felt very hit and miss which explained the reason there were more supplied than required.
The quality of loads of their flexes made the Chinese crap look positively beautiful.
I know we tend to complain about some of our electrical accessories but my limited experience of North American kit makes me realise ours is not bad.
Australian sockets are much like ours regarding terminals and you can certainly get two wires in.
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