ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades Polarise schuko?

The safety groups have made ever stricter rules about plugs and sockets (shutters, partially shielded pins on BS1363 plugs, etc.), yet the lampholder remains pretty much the same design as it's been for many, many years (odd items such as MK's type with the isolated pins notwithstanding).

I don't believe there's anything basically wrong with lampholders, but it's rather curious that the normally over-zealous committees don't seem to have turned their attentions to it as yet.

Well our overzelous committee seems to be about to go on a mad RCD spree. They're reviewing the RCD requirments with a view to making them much tighter. A single RCD on the panel won't do.

Aside from cutting the current flow to both contact pins when the bulb is removed, how else can you redesign a lampholder without upsetting the entire existing lightbulb industry and p---ing people off when they have to go out and buy new lampholders to accomodate the new types of bulbs?

A neat lampholder would be the bi-pin plug-in CFL sockets (the little U-Tubes for some table lamps) with a few minor modifications (recessing the contacts in even deeper and maybe shuttering them).

Or how about something that twist-locks (like the NEMA type Twist-Lok plugs used in the 'states)? That way the bulb won't fall out when flipped upside down.

Sven et. al. Didn't we have a discussion about improved lampholders some time ago? A new and better type would indeed be a good idea.

djk,
I noticed that the manufacturers are now pushing for the RCBO. Or from a rule makers point of view: One RCD per MCB. I think it's a good idea hadn't it been for the price Strange: A (portable) RCD costs less than €10 and a breaker €5. But integrated into a RCBO the price jumps to €50!

Concerning the polarisation: Millions of 230V line-to-line socket will remain in use for years to come. And there must be hundreds of millions of unpolarised sockets in use today.


So far I agree!


Appliance plugs fit. Not extension cords or plugs fitted by the user. You would have a very hard time finding a rewireable plug that fits French sockets here.

Other than for lamp sockets, what other reason would an AC system need to be polarised?

The US started polarising the non grounded two conductor appliance cords a few years back by making one blade wider than the other. and that was primarily done for lamp safety.

But, with both conductors being the same colour, it is a 50-50 chance that the wires are connected properly anyway. And for sure if a lamp owner replaces the socket, there is no guarantee the connections will be correct afterwards. So, what is really gained?

If I'm not mistaken, lamps don't use the Schucko plug anyway, they use the smaller europlug. So, why modify the schucko plug just for lamps? If safety is a concern with the lamps, then it is up to the lamp manufacturers to come up with a safe lamp socket. That for sure would be cheaper, no?

Only one single word about portable lamps: double pole switches!
And voila the only solid argument for polarised plugs deflates like a car tyre.
Another thing, I think with BS1363 shielded pins and shutters are indeed a good idea. Old BS1363 plugs were indeed quite scary as you have to grip them pretty close to the pins when pulling them out. And the holes in the socket are awfully large.

Lamps that come from the factory are fitted with the Europlug. However, lamps that have been rewired by the user have Schuko plugs or the old round plug, since there is no rewireable and ungrounded plug for double insulated appliances. Europlugs are always moulded with a cord. I would think this legal requirement is intended to prevent people from using an ungrounded plug on a grounded cord.

There are some national plugs that are rewireable and look like the europlug, e.g. the French 6A plug or Italian 10A plug.

C-H said:


They still sell those old round plugs? Hmm...

I'm sure replacement Europlugs have got to be sold in _SOME_ place. There's a company in Spain that maufactures them and a few others (don't know the names since they only stamp a logo on the housing).

Anyway, here in New York City (of all places!) two lighting stores sell replacement Europlugs. It's a little clamshell that snaps together.

I've never bought one so I don't know how the wires attach to the pins. Why would anyone buy a Europlug in the states (unless you're weird like me )?

I have another replacement type Europlug that is non-rewireable. The pins get crimped onto the lampcord and then the entire assembly gets snapped into the housing. I used one of these on the flex of an old 120/240 volt Philips portable radio.



Of course, once you attach one of these plugs and then in the far future it comes time to replace the cord, you can't reuse the plug and attach it to the new length of flex....a total waste.

Also, why would someone use a two-ping plug o n a grounded cord? Usually the three-wire cord is much thicker than what could fit in the hole of the housing of a replacement Europlug.

But then again...the fools that would do that are the ones that use a molded plug with a few inches of flex stump and splice it to the cordset of their appliance with black tape -- they don't want to spend minimum $3.00 for a three-pin heavy-duty plug.

[This message has been edited by SvenNYC (edited 09-05-2003).]

My electrician told me the crimp-on Euro plugs have been outlawed years ago here in Austria but didn't give me reasons. I suspect some bloody idiots didn't crimp them on but just stuffed the wire into the holes and naturally the assembly eventually failed. I still have 1 or 2 unused ones around, they were sold in black, brown and white, male and female.
Rewireable Euro plugs are illegal for some really weird reason, one reason is supposed to be that plugs for double insulated appliances must not have any exposed screws ('cause these screws would have to be grounded and then it isn't double-insulated any more yadda yadda yadda... For the same reason it's illegal to fit a Schuko plug to a device with Euro or contour plug. The only legal way is to buy a new cord with molded plug. However I doubt _anyone_ really sticks to that piece of code. At least it's good for week-long discussions at de.sci.ing.elektrotechnik).
These crimp Euro plugs easily accommodate round 2x1mm2 flex, so it would be easy to fit 3x0.75mm2 flex which is even thinner.
Reminds me of a story. I once bought a 1949ies vintage vacuum cleaner.At the first lokk I thought they simply spliced a pice of flex with a Euro plug to the old rubber cord. however, a closer look revealed they had done much better than that. They had cut the old rubber cord about 30cm from the appliance connector (the rubber had about the consistency of chewing gum). Then they spliced a short piece of white 2x0.75mm2 flex (twist'n tape, they didn't even bother to tape the neutral splice seperately, they taped the black splice, then did the blue-grey splice and taped the entire splice). Then they spliced the white cord to a long piece of 3x1mm2 flex (same method). Finally they spliced the black cord to the reamainder of the white cord which had a molded Euro plug. AARRGH! How stupid can people be? To think they could have saved 3 (!) spliced if they had just connected the 3x1mm2 cord to the appliance plug and fitted a new plug!

It's no secret that I'm a not a fan of the whole-house RCD approach. I would much rather see individual devices, like the American GFCI, for each circuit. At the moment, however, the cost of an RCBO makes it a very unattractive proposition for TT systems where every circuit needs RCD protection.

On the polarization issue in general, I think that the British IEE sometimes gets carried away.

Let's look at something like a double-insulated hair dryer or electric drill. The IEE would object to it being run on a reversible plug because a single-pole switch on the unit could end up being in the neutral.

So what? The switch still breaks the circuit and turns off the appliance. Yes, it leaves the motor connected to the hot side of the line, but what does that matter in this situation?

By the way, does anybody know exactly when the polarized two-prong NEMA plugs were introduced?