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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?

A.S.
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  • 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. – DerStrom8 Apr 20 '18 at 17:26
  • 2 or 3 pin?..... – Tony Stewart EE75 Apr 20 '18 at 17:40
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    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. – Hot Licks Apr 20 '18 at 19:38
  • 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. – A.S. Apr 21 '18 at 01:45
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    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. – Matteo Italia Apr 21 '18 at 19:00
  • Nema 5-15 female is what they are called – LucM Apr 22 '18 at 17:10

4 Answers4

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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

DerStrom8
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    +1 Good options for one-off to low volume. – Spehro Pefhany Apr 20 '18 at 17:36
  • Out of curiosity, do you happen to have a part number or online supplier for the enclosure with integrated main? – Simon Marcoux Apr 20 '18 at 18:12
  • @SimonMarcoux The one pictured is the PM2314T03XWT from PolyCase. There are a number of different styles, including two-prong versions, three-prong versions, ones with a mounting tab/hole, and ones without. https://www.polycase.com/pm2314 – DerStrom8 Apr 20 '18 at 18:22
  • That last one looks dangerous for some reason... – Michael Apr 20 '18 at 19:39
  • @Michael I'm inclined to agree, but provided the designer really knew what they were doing, it probably wouldn't be an issue. All sorts of professional products do this already. My biggest concern would be how to physically support the pins. I wouldn't trust the solder alone. Personally I would go with the enclosure with built-in plug. That seems like it would be the safest and most reliable option. – DerStrom8 Apr 20 '18 at 19:56
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    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.... – rackandboneman Apr 20 '18 at 23:31
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    @rackandboneman Apple had to recall the original chargers for the 2008-era iPhone due to just that problem, per http://www.iphonehacks.com/2008/10/recall-details.html – zwol Apr 21 '18 at 00:06
  • The "PCB-mount" example requires rivets or nuts/bolts to secure it, it's not just solder-and-forget. – Whit3rd Apr 21 '18 at 00:30
  • That second option (PM2314T03XWT) is very close to what I am looking for, perhaps "pcb mounted" isn't quite what will work best for me after all. Are you aware of any connectors like that which do not include the case, only the connector? Or a larger case? This case is too small for my application. – A.S. Apr 21 '18 at 01:56
  • @A.S. There are hundreds of designs like this-- enclosures with integrated mains plugs. It's frowned upon here to give recommendations for products and where to buy them, so all I can say is search for "enclosures with integrated mains plugs" or something similar and you'll find all sorts of shapes and sizes. – DerStrom8 Apr 21 '18 at 02:37
  • @DerStrom8. There are low current and high current versions of the IEC connector, which must have the correct plug to fit. –  Apr 21 '18 at 06:14
  • @Sparky256 Of course, and if the designer chooses to use an IEC connector he or she must select the correct version based on their circuit's requirements. – DerStrom8 Apr 21 '18 at 10:51
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    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. – Harper - Reinstate Monica Apr 21 '18 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

D Duck
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  • 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. – Dai Apr 21 '18 at 22:51
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    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! – zwol May 01 '18 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.

Spehro Pefhany
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  • Are individual connectors (just the copper) available to be then inserted through a plastic case? – A.S. Apr 21 '18 at 01:57
  • 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. – Spehro Pefhany Apr 21 '18 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.

Harper - Reinstate Monica
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  • 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. – mike65535 Apr 24 '18 at 21:19