Australian standard AS/NZS 3112:2000 has been updated and as of April 3, 2005 requires the use of insulated line and neutral pins. The use of the insulated pins is being implemented in order to lower the risk of electrocution and shock as a result of inadvertently crossing the live pins.
That's a good improvement. Like the old unsheathed pin BS standards (1363 & 546) it seems to be easy to accidently contact the pins.
Grounded recessed plugs (Schuko/French) have been the only ones that have prevented this from happening from day 1 and as far as I know 2-pin Europlugs have had sheathed pins for a long time too, far before BS1363 got them added on.
Plugs intended for a European recessed socket inserted into a flat non-grounded socket can be quite scary, old sockets often contact the pins when they're only very partially inserted too.
NEMA plugs arn't great in this regard either. Isn't there a sheathed version required in some far eastern countries? (Japan?)
[This message has been edited by djk (edited 09-22-2003).]
#138682 - 09/22/0306:37 PMRe: New requirements for AS/NZ plugs
The ESB opposed their use here as an offical standard until the pins were sheilded!
Apparently the standards athority was pushing them but the ESB prefered recessed schuko on safety grounds and because it was designed for 16A appliences at 220V which made sense! Considering that a 3000W applience will quite often blow the fuse in a 13A plug here if it's being fed with a steady 220V. The technical standards committees got all flustered over polarity and fusing while the ESB had more sense.
[This message has been edited by djk (edited 09-23-2003).]
#138684 - 09/23/0308:32 AMRe: New requirements for AS/NZ plugs
Schuko plugs have one more advantage only a recessed system can offer: They hide any arcing from the user. I have had some quite nice flashes plugging in old ungrounded plugs, but with Schuko plugs they don't get out of the receptacle, so there's far less risk of burning something. Flat plugs have been around for some time, but at the moment they were called Euro plug they had sleeved pins.
#138685 - 09/23/0309:39 AMRe: New requirements for AS/NZ plugs
BS1363 contacts are so far back in the socket you never see arks either though.
PaulUK: just out of curiosity in Ireland I notice a lot of burn damage around the live receptical of sockets, including well known brands like MK ! Also notice it around the live pin on plugs of heavy appliences quite a lot. E.g. it wouldn't be THAT unusual to see it on a socket where the kettle is plugged in or the dryer.
Those BS fuse cartridges and holders get very hot. I always think the way the fuse makes contact with clips is pretty flimsey in those plugs.
Is that common in the UK? Or are we getting a slightly higher current loading on the pins due to the lower voltage?
[This message has been edited by djk (edited 09-23-2003).]
#138686 - 09/23/0310:53 AMRe: New requirements for AS/NZ plugs
I wish they would do the sheathing on the American type plugs. The Japanese (who use the same type of plug config) already do it on theirs:
The pins are the same dimensions, so if the Australians can do it, so can the American plug manufacturers.
Also, it would force plug contact manufacturers to drop the silly folded sheet metal blade design that is easily bent and damaged and instead opt for the sturdier solid blades like the Aussies have done.
Unfortunately our standards are not as enforceable...unless you get the idea into the Chinese manufacturers' heads who currently think that ALL American plugs molded onto cordsets have to be polarized to get UL listing... even when its a tape recorder cordset with the figure-8 connector on the other end is NOT polarized!!!
#138687 - 09/23/0303:34 PMRe: New requirements for AS/NZ plugs
It seems as though it's not just imported equipment being fitted with polarized plugs where they're not really needed.
I have a recent-ish Dremel (120V American-market version) and it has a polarized plug. The tool is made in U.S.A., although I suppose the cordset might have been imported. It's double-insulated with black and white cores rather than SPT type, so are polarized plugs being used on all such identified cordsets now?
just out of curiosity in Ireland I notice a lot of burn damage around the live receptical of sockets, including well known brands like MK ! Also notice it around the live pin on plugs of heavy appliences quite a lot.
I see it a fair bit here too. Some of the cheap BS1363 plugs can get very hot under heavy load, and as you say it seems to be the fuse and clips which cause the problem.
I advise people to use those "el cheapo" plugs on their bedside lamps, radios, etc. if they wish, but recommend a better make such as MK for the washing machine, tumble dryer, heaters, etc.
Schuko plugs have one more advantage only a recessed system can offer: They hide any arcing from the user.
Most people here would probably argue that visible arcing shouldn't be a problem due to the majority of outlets have integral switches.
Switched receptacles are so much the norm here that some people are under the impression that the regulations require them, at least in domestic work. The only time the IEE Regs. specified an integral or adjacent switch for general purpose outlets was on DC systems.
[This message has been edited by pauluk (edited 09-23-2003).]
#138688 - 09/23/0305:11 PMRe: New requirements for AS/NZ plugs
My Dremel Moto-Tool is also like that. Ditto a double-insulated electric drill I have. Both also have the flimsy folded-sheet metal blades so they will someday be replaced by sturdier (non-polarized) caps.
It is easier to find non-polarized replacement plugs in hardware stores anyway.
The cordsets are available in un-polarized versions, but I guess the manufacturers just want to play it easy and safe.
What is the difference between the cheapie plugs and the MK brand? I've used the MK brand British plugs and like the fact that they have American style wrap-around terminals.
Other brands don't. They have those grub-screw type things instead. Is this the reason? I've used the second kind also and you have to double and bunch up the wire so the screw can bite into it securely.
#138689 - 09/23/0307:33 PMRe: New requirements for AS/NZ plugs
The MK wire terminals are certainly well designed. The nuts with captive retaining clamp and washer have been used on MK plugs since at least the 1950s.
As you say, most other brands have the screw and hole method, and doubling over the wire is just about essential on the smaller size conductors.
The overheating problem seems to be from the fuse clips. The MK type (and other good brands) clamp the whole length of the fuse's end cap, whereas many of the cheap brands seem to have rather thin clips which only "spot grip" the caps in a couple of places.
If you run say 2 or 3kW heater for a half hour, you can often feel the right-hand side of the plug getting quite warm.