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enter image description hereI have a USB fan connected to a USB plug (and have tried 3 different USB plugs). It will not work in either bedside socket, but will work in any other socket. Other things work fine in the bedside sockets. Anyone have any idea how this is possible?

One other thing, when I pull the plug out of the socket when the fan isn't working, it starts working really briefly

Location UK, 3 pin plug.This is the fan with its cable and the thing on the end is the USB thingy (would love to know what it's called, USB cable?

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    please include a picture of the fan, usb plug and socket. and what "other things" work fine? could be a poor throng mating, Try with an extension cord between the receptacle and usb.
    – P2000
    Feb 6, 2023 at 16:15
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    I mean prong, not throng or thong
    – P2000
    Feb 6, 2023 at 16:21
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    Outlets do wear out. Plugs do get bent. Bad connections can happen, and when bad enough can be a fire hazard. I'd suggest taking this as a warning to replace that outlet.
    – keshlam
    Feb 6, 2023 at 16:23
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    now I'm confused ... you have an electric blanket that connects to a USB port? ... what exactly do you mean by USB plug? ... tried 3 different USB plugs ... are you not talking about an outlet with USB ports built in?
    – jsotola
    Feb 6, 2023 at 16:44
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    @dandavis -- UK (BS1363) plugs can't be messed with in that way Feb 7, 2023 at 3:42

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I suspect the cause of the malfunction is a poor mating between the plug and the receptacle.

Some lower cost plugs may have prongs that are out of spec (too small, too thin).

The solution in this case is to get a better plug with better grab.

North American prongs can be bent a bit for improvement, but this is less so with UK prongs.

From the comments: "Some lower cost sockets have contacts that are too close to the face. So the metal parts of the prongs pass the contacts and after inserting the plug fully, only the insulated parts of the plug touch the conducting parts of the socket. A phenomenon quite unknown in countries with solid-prong plugs US, but common with UK and Europlugs. The problem is neither width nor height, it's depth. Also, UK prongs are notoriously tough, they're too tough to be bent outside of workshop and if they are bent the plug no longer enters the sockets" - @Agent_L

A different plug with shorter isulation "socks" at the prongs might do better.

As a workaround you could apply a few layers of electrical tape to the face of the plug at the pronged side, as a spacer, so that the plug makes better electrical contact while not fully inserted. This requires some judgement to ensure the plug is still firmly held by the socket and that the metallic parts of the prongs remain not exposed.

An alternative workaround is to use a short extension cord, which possibly better mates with the USB adapter plug and/or receptacle.

Sometimes receptacles wear too, but since this is a bedroom and also since other plugs seem to work fine, I would suggest a closer examination of the plug.

Fixing this problem is important, because poor connections can cause arcing even at low currents, which can cause house fires. Resistive heating is another hazard if it is indeed a worn receptacle and a high current device like a space heater or computer is plugged in.

And contrary to some information on the web, the holes in the North American prongs have nothing to do with indexing (i.e. "holding") the plug firmly in the socket, as some form of detent. They are allowed by NEMA and their purpose is to aid in mold alignment during manufacturing. So, at least in North America, a lack of such holes, as one may see in some USB or other plugs, does not make a bad plug or cause poor mating.

Ref: Alec Watson, Technology Connections, https://www.youtube.com/watch?v=udNXMAflbU8

enter image description here

Image: https://www.reddit.com/r/mildlyinteresting/comments/arxts5/my_new_phone_charger_doesnt_have_the_little_holes/

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    Those "detent" holes actually don't do anything for retention. There is no real reason for them to be present actually, and they don't indicate any info about the quality of the plug. see youtube.com/watch?v=udNXMAflbU8
    – dandavis
    Feb 6, 2023 at 22:19
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    @dandavis those TC vidoes are excellent, thanks for pointing this one out. I updated my answer. Nothing changes for the OP, but I'd rather not have wrong information in my posts.
    – P2000
    Feb 6, 2023 at 23:06
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    And some lower cost sockets have contacts that are too close to the face. So the metal parts of the prongs pass the contacts and after inserting the plug fully, only the insulated parts of the plug touch the conducting parts of the socket. A phenomenon quite unknown in countries with solid-prong plugs US, but common with UK and Europlugs.
    – Agent_L
    Feb 7, 2023 at 10:49
  • Indeed @Agent_L, OP could bend the prongs a tiny bit and hope for better tension/friction grab, simply buy a different brand adapter plug with (hopefully) shorter insulation "socks". Good point. Will update answer.
    – P2000
    Feb 7, 2023 at 14:33
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    @JimStewart I doubt it. I have German prongs at hand but no UK prongs, and I would think they are similar in that the prong is equal thickness in metal and insulated part so shaving off the insulation would expose the metal but it would have less thickness. This could work if the receptacle has enough flex & grab, or pose a loos-contact hazard.
    – P2000
    Feb 7, 2023 at 17:37

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