UK power regulations - potential safety issue

[Agrippa]

At the risk of spinning this thread out even longer, exactly what is the safety issue here?

There is no easy way to say this - I think you will have to read it all from post #1 onwards, sorry 

As we say in Jockshire, "Aye, right "

[DELETED]

Is a "shaver adapter" a different beast from a general 2-3pin adapter?

...few years ago they were.  There was a mm or two different on pin spacing to prevent you from using them as power adapters, I've seen shaver adapters melt many times because you could still force the pins in -or you aren't using them for a shaver, just use the proper adapter, theyre not expensive.

[Ancient Hermit]

Is a "shaver adapter" a different beast from a general 2-3pin adapter?

...few years ago they were.  There was a mm or two different on pin spacing to prevent you from using them as power adapters, I've seen shaver adapters melt many times because you could still force the pins in -or you aren't using them for a shaver, just use the proper adapter, theyre not expensive.

And then there is this advice from a well respected retailer, and I quote:

"P114 POWERCAB POWER SUPPLY

An additional or replacement DC power supply for the Power Cab system and other model railroad uses. Input 120VAC/220VAC, output 13.5VDC  2A peak. CE approved requires Shaver adaptor  2 to 3 pin. "

You can easily see how these things may go awry: Your advice is good, the retailer's advice could certainly benefit from some review.

I don't for a minute suspect they would be the only retailer offering such poor advice either. It looks like it could have been copied and pasted from an American source, (the word railroad, and the spelling of adaptor instead of adapter is a good clue here) and the original author won't by default be so well versed in our local regulations. The product may not have even been targeted for the UK market in the first place.

These subtle differences should not sensibly be left to chance, and the purchaser is not always likely to realise the potential problem lurking within such advice, especially if a small boy spending his gifted Christmas loot for example.

I'd just like to see model railways being something one could safely purchase and operate. Anything that helps this become the norm is surely something to welcome?

Stay safe one and all.

[PostModN66]

An additional or replacement DC power supply for the Power Cab system and other model railroad uses. Input 120VAC/220VAC, output 13.5VDC  2A peak. CE approved requires Shaver adaptor  2 to 3 pin. "

Still don't really get it - if output is 2A at 13.5 v, input current at 250v would be of order 100mA.
Can a shaver socket really not handle this without melting?  What current does a shaver draw?!

Yours genuinely not really understanding........Jon 

[PaulCheffus]

An additional or replacement DC power supply for the Power Cab system and other model railroad uses. Input 120VAC/220VAC, output 13.5VDC  2A peak. CE approved requires Shaver adaptor  2 to 3 pin. "

Still don't really get it - if output is 2A at 13.5 v, input current at 250v would be of order 100mA.
Can a shaver socket really not handle this without melting?  What current does a shaver draw?!

Yours genuinely not really understanding........Jon 

Hi

I certainly have a problem then as my shaver plug is fitted with a 1A fuse and it is only used for charging my shaver. I too am puzzled why 100mA is going to cause a meltdown.

Cheers

Paul

[Ancient Hermit]

An additional or replacement DC power supply for the Power Cab system and other model railroad uses. Input 120VAC/220VAC, output 13.5VDC  2A peak. CE approved requires Shaver adaptor  2 to 3 pin. "

Still don't really get it - if output is 2A at 13.5 v, input current at 250v would be of order 100mA.
Can a shaver socket really not handle this without melting?  What current does a shaver draw?!

Yours genuinely not really understanding........Jon 

I have a shaver adapter to hand. It bears the following: "FOR UK SHAVERS AND TOOTHBRUSHES ONLY" - this is moulded/embossed into the front panel of the unit. (note that is not cheap to do so clearly it must be a needed/required thing)

It says that because that is what the regs call for it to say.

A model railway is clearly not a shaver or toothbrush of any sort.

It's pretty straightforward in my view.

[Jonny]

This is all thats needed to convert 2 to 3 pin. Has built in fuse as well. 

http://www.amazon.co.uk/gp/aw/d/B0000934J2/ref=pd_aw_sbs_ce_1?refRID=07N1RKV26DS7DR0FYJ96

Jonny

[Ancient Hermit]

[smg id=20527 type=full align=center caption="image"]

Yeah, it's hard to imagine how, but there it goes again!

Wish I had never noticed the problem, and if I ever find another problem like it you can be sure I would probably just keep it to myself.

[keithfre]

Can a shaver socket really not handle this without melting? 

I don't think we're talking about a shaver socket, Jon. That will have a low-power transformer built in to isolate it from the mains.

I suppose if an adapter were to be short-circuited it could melt, but not if it's fitted with a suitable fuse.

[warlokk]

All British domestic dwellings should have RCBO protection fitted to the sockets which should trip within 40ms giving much better protection than having to rely on a fuse popping. Personally I would never use any form of adaptor to a standard UK plug. If I was unable to cut off the supplied plug and replace with a UK one because the transformer had the pins built in I would rather replace the power supply unit and risk voiding the warranty

[RussellH]

Found this...

Items which do not need a plug when sold:-
5. Any appliance which is fitted with a plug transformer but note that the technical aspects of BS 1362 must still be met.
That's in here...  http://www.norfolk.gov.uk/view/ncc048437

Further reading on "the shaver adapter"...

The purpose of these adaptors is to accept the 2 pin plugs of shavers, they are required to be marked as such. Shaver adaptors must have a 1 Amp BS 646 fuse. They must accept UK shaver plugs complying with BS 4573 and also Europlugs and American two-pin plugs.

That's from here... http://en.wikipedia.org/wiki/BS_1362#Fuses

From a practical point of view a small item (rated for 230v use) plugged into the shaver adapter will work (may not look nice, hang at an odd angle and eventually the pins may snap off etc). But, IF it develops a fault and IF your shaver adapted hasn't got a fuse it will be exposed to a fault current of around 90+amps (assuming the ring main is supplied from the standard 32Amp B type MCB). That's ample for a big black mark and/or fire.

If you want to use the shaver adapter - please make sure it's a fused one.

Ideally as per warlokk's suggestion, get an equivalent PSU with the correct plug from a reputable supplier.

Russ

[Agrippa]

In other words just buy the correct thing for UK use...