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I am working on a self device which will plug into the wall, similar to this Wifi extender.

I am having trouble finding a way to attach the AC connectors to my design. I am considering mounting a connector directly on the PCB, something like this example. This one is a bit too large through (the black housing).

Do pieces like the one I am looking for exist? Or what is another way I may consider making the AC outlet connection?

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  • \$\begingroup\$ They do exist, but they're a fairly niche item. I would actually recommend using a PCB-mount IEC connector instead, if you don't mind needing a cord. \$\endgroup\$
    – DerStrom8
    Apr 20, 2018 at 17:26
  • \$\begingroup\$ 2 or 3 pin?..... \$\endgroup\$ Apr 20, 2018 at 17:40
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    \$\begingroup\$ The problem is that the forces placed on such a device can be substantial, as it is plugged/unplugged, and a PC board, alone, is not enough to support it. It would never pass UL certification. \$\endgroup\$
    – Hot Licks
    Apr 20, 2018 at 19:38
  • \$\begingroup\$ A cord is not an option in this case, it must be outlet/wall mounted. Either 2 or 3 pin would be fine for now, and as a prototype it doesn't need to pass any certifications. Maybe a later version I would consider the stricter requirements. \$\endgroup\$
    – A.S.
    Apr 21, 2018 at 1:45
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    \$\begingroup\$ I'm by no mean an electronics product developement expert, but if I were designing such a device I would try to decouple the main PCB from the specific wall plug connector, to avoid potentially having different versions of the PCB for each and every wall plug that exist in the world. \$\endgroup\$ Apr 21, 2018 at 19:00

4 Answers 4

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If you don't mind using a power cord, I highly recommend using a PCB-mount IEC connector instead. These are very common and readily available.

enter image description here

If you absolutely must have a device that plugs directly into the wall, I recommend building your Wifi extender into an enclosure with an integrated mains plug:

enter image description here

Individual PCB-mount mains contacts do exist, but are fairly uncommon and difficult to source. I recommend using one of the above options instead.

EDIT: It looks like Heyco (a company owned by PennEngineering) makes PCB-mount mains blades:

https://www.heyco.com/Power_Components/pdf/PCB-Contacts.pdf

enter image description here

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    \$\begingroup\$ +1 Good options for one-off to low volume. \$\endgroup\$ Apr 20, 2018 at 17:36
  • \$\begingroup\$ Out of curiosity, do you happen to have a part number or online supplier for the enclosure with integrated main? \$\endgroup\$ Apr 20, 2018 at 18:12
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    \$\begingroup\$ I guess if you manage to break a solder joint (and I assume you eventually WILL when subjecting it to the manhandling plug-in devices like that usually receive), you can leave a bare strip of metal plugged into a live outlet behind when unplugging - to add insult to injury, it will be right in your fingertip slip zone when pulling the device.... \$\endgroup\$ Apr 20, 2018 at 23:31
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    \$\begingroup\$ @rackandboneman Apple had to recall the original chargers for the 2008-era iPhone due to just that problem, per iphonehacks.com/2008/10/recall-details.html \$\endgroup\$
    – zwol
    Apr 21, 2018 at 0:06
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    \$\begingroup\$ Insertion force on mains power plugs can be brutal. I just had to arm-wrestle one that had at least 20 pounds of insertion force. I thought I would break the adapter, and it's Apple! ----- And if your adapter shatters, lacerating AND shocking the user, well, that's why UL listing is such a complicated process. \$\endgroup\$ Apr 21, 2018 at 14:31
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Make an enclosure like this USB power supply and then use the available (google "interchangeable AC pins") slip on pins for different markets. The forces on the pins are not transferred to the pcb. enter image description here

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  • \$\begingroup\$ This is probably the best answer - and good slip-on connectors are designed to break-away under sufficient force in a way that doesn't expose live contacts to users. \$\endgroup\$
    – Dai
    Apr 21, 2018 at 22:51
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    \$\begingroup\$ I like this answer, but if the device is going to be sold to the public, make sure it can handle both 120 and 240VAC input! \$\endgroup\$
    – zwol
    May 1, 2018 at 19:46
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Usually the manufacturer will use stamped metal terminals that are retained by an injection-molded case (made of appropriate fire-retardant resin) and connect directly to the PCB.

Both can be custom parts, but MOQ and/or tooling costs will be large.

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  • \$\begingroup\$ Are individual connectors (just the copper) available to be then inserted through a plastic case? \$\endgroup\$
    – A.S.
    Apr 21, 2018 at 1:57
  • \$\begingroup\$ The Heyco ones shown by @DerStrom can be (and probably should be) supported by slots in a plastic case as well as the PCB. I've also seen similar products on offer from Asian suppliers. \$\endgroup\$ Apr 21, 2018 at 11:29
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How many are you making? If able, I suggest making your device hang off a wall-wart that somebody else has already gotten UL listed.

This will save you the risk of fire or shock, and the Byzantine, time consuming process of getting a mains power device UL listed ...

The first example (for single/small quantity) that comes to mind is the 5w or 10w Apple chargers, which output USB and are readily available in quantity 1-30 on ebay.

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  • \$\begingroup\$ This is a very real problem and should not be ignored. If you plan to go into production, a purchased wall wart will save you untold effort and expense. \$\endgroup\$
    – mike65535
    Apr 24, 2018 at 21:19

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