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New design of mains plug?

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old mart30/03/2020 14:44:38
3345 forum posts
208 photos

I just got this little 9-24 volt dc power unit through the post today. It works and has a built in volt meter. I was not so impressed by the mains power plug, however, it is so small it has no room for a fuse. Having used the fused plugs for exactly 60 years, I intend to replace it with a proper one and fit a 1 amp fuse.


Bo'sun30/03/2020 14:49:51
514 forum posts
2 photos

Interesting! More details please.

SillyOldDuffer30/03/2020 15:10:48
7549 forum posts
1680 photos

I would change it too, but it may contain a sealed in fuse, ie if the built-in fuse goes pop, the unit is thrown away, not repaired, ever.

Can you open the plug up to see what's inside please? If it doesn't contain a fuse, the whole power-supply is suspect. Is it from the 'too-cheap' family! Is it CE marked?

What fun!


duncan webster30/03/2020 15:37:33
3508 forum posts
63 photos

If it hasn't got a fuse in the plug it's illegal, more to the point it's potentially dangerous, If you bought it from a UK supplier shop him to trading standards, and if you haven't already cut the plug off I'd send it back for a refund. If they miss such a basic point what else is going on in there. It should conform to BS1363.

If you bought it direct rom China, let this be a learning experience!

Ian P30/03/2020 15:40:13
2524 forum posts
102 photos

If you bought that from a UK supplier then trading standards should be advised. It certainly does not look to comply with current electrical standards.

The plug is the most obvious breach of CE regulations and should be changed. My concern though is whether what is inside the enclosure is safe to use (I'm being serious). We have no idea what you intend to use it for but potentially under fault or failure conditions there is always the possibility that mains voltage could be present on the output connector.

Ian P

Neil Wyatt30/03/2020 15:40:42
18776 forum posts
733 photos
80 articles

As far as I can see it's illegal:

"The distance from any part of the line and neutral pins to the periphery of the plug base must be not less than 9.5 mm."

This is to minimise the risk of fingers reaching around and touching the pins.

If that has a CE it shouldn't have one.

I'd open it up and check there is safe separation between the live and output sides of that.


Journeyman30/03/2020 15:45:15
1033 forum posts
199 photos

It's a BangGood special! I'd bin it...


Ian P30/03/2020 15:45:38
2524 forum posts
102 photos

Its not possible to visually check separation of the transformer.

Ian P

Martin Connelly30/03/2020 15:47:24
1888 forum posts
203 photos

It may be CE marked but there is a subtle difference in letter spacing between the EU mark and the Chinese Engineered mark.

Martin C

Ed Duffner30/03/2020 15:50:54
830 forum posts
94 photos

But remember China has it's own C E mark with a gap between the C and E, for China Export, as I understand it anyway. As opposed to CE for Europe.


Mike Poole30/03/2020 15:58:59
3071 forum posts
72 photos

They are lethal, cut it of and fit a proper plug with the corrrect fuse. I have had a few of these turn up on devices like hard drive enclosures and other computing related equipment, they are all in the bin, it does raise doubts about the rest of the engineering of the equipment but as they are attended devices and as long as they work I don’t worry too much. I would have second thoughts about a device that would be powered for long periods or permanently on and unattended. People will slag off China but remember they also manufacture a lot of top quality electronic equipment but usually with a top brand name as well.


Edited By Mike Poole on 30/03/2020 15:59:45

old mart30/03/2020 16:07:12
3345 forum posts
208 photos

I have just removed the plug, the wires are black for live and blue for neutral. I cut the plug up and the wires go directly to the terminals, there is no fuse. I also tried the insulation at 20M, there is no continuity between the mains input wires or between them and the dc output. There are no CE marks of any type, it came direct from China.

Edited By old mart on 30/03/2020 16:10:39

not done it yet30/03/2020 16:41:44
6322 forum posts
20 photos

If you must use it, don’t leave it plugged in and switched on at the socket - it is powered all the time, despite it having a switched potentiometer - it only switches the output (and the display).

Too many transformer wall warts have spontaneously burst into flames. What is the transformer rating, if of that type (it must be shown, by law)? Lower grades are not allowed to be sold, these days, I believe, as transformer losses can be considerable.

Edited By not done it yet on 30/03/2020 16:43:28

Ian McVickers30/03/2020 17:18:36
213 forum posts
109 photos

That type of plug has been around for a while now. Cant understand why they havent been banned yet. Have a look on They are shown on the first page.

Bazyle30/03/2020 17:43:36
6038 forum posts
220 photos

It isn't the plug that is a threat unless you expect it to b used by children or halfwits and you could easily clue on a plastic disc with 3 holes in it if you are really worried. The danger as mentioned above will be fire especially as it is advertised as 70W . It is switched mode so no transformer and probably fully potted inside which actually helps heat dissipation. Of course there are lots of non CE items being imported as long as you allow advertising and direct shipping of electrical goods. What do you expect - trading standards to open every package arriving from China?

herbert punter30/03/2020 17:55:25
128 forum posts
1 photos

Any apparatus supplied with this plug is probably going to be dangerous.

This non compliant design plug will not have a certified mains lead and usually the conductors are too thin for safety.

The only thing to do with it is to cut the lead into short pieces or burn it and bend or break the plug pins so that it cannot be inserted in a socket.

i would smash up the rest of apparatus and dump it in the recycling.


vintage engineer30/03/2020 17:58:46
254 forum posts
1 photos

Doesn't CE stand for China Export?

Former Member30/03/2020 17:59:58
1329 forum posts

[This posting has been removed]

DrDave30/03/2020 18:01:29
230 forum posts
46 photos

I have never understood the British love of fused plugs: most of the world seems to be happy with unfused plugs. None of the electrical equipment that I bought when I lived in Switzerland has a fused plug, for example.

Other than the regulatory requirement here (and after all it does sound like a good idea), can anyone explain why Britain and the colonies have this different plug philosophy?

Former Member30/03/2020 18:02:17
1329 forum posts

[This posting has been removed]

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