(Preemptive apology if this is the wrong place to ask; pointers to the right place appreciated)

I've thrown together a device using a Raspberry-pi, touchscreen (plugs into pi) and small monitor type thing which has its own power cord and brick. I've for the time placed everything into a small radio shack project box.

Right now, there is an extension cord with 2 outlets on it that run into the box which the pi and other device plug in to. The idea is that there is only 1 cord that needs to be plugged in for power; would much prefer if there weren't multiple power cabled needed.

This device is not so much to sell for now, but as an adjunct to an existing (very small; read: no budget) business. I have no idea where to go from here. Several google searches for "selling electronic device" etc have provided no help.

I'm trying to determine if there are regulatory or other regulations that this would fall into. FCC? UL? CE?

NB: I'm in the US with no immediate plans to use the device overseas.

Where would be a good place to ask for details? If the answer is lawyer up, what kind of lawyer should I look to talk to?

Also, are there resources I could look to to try and find a better way to power the devices? The Pi is powered via mini-usb and a transformer that came with it (think iDevice power brick). The block did not fit into the project box as it was, so I had to disassemble it. This makes me nervous because fire. What would be the recommended way to break out power from a single cable from wall to multiple devices?

  • \$\begingroup\$ Why not keep the external PSU as such? It is safe and it radiating noise into the Pi is minimal. \$\endgroup\$
    – jippie
    Dec 9, 2013 at 21:17
  • \$\begingroup\$ Thanks, and sorry for not being clear. I'd be fine with leaving it as is if 1) it fit in the box, and 2) running a power strip into the box and plugging it (and another device) into it didn't seem like a hacky/bad idea/perhaps illegal. \$\endgroup\$
    – canterman
    Dec 9, 2013 at 21:29

1 Answer 1


Definitely DO NOT dismember the AC adaptor and imbed it in your device. Use a UL-approved wall-wart power supply (or an iDevice power block) as-is to provide power to your Pi, and provide power to the second device from the Pi box.

If you run 120VAC into your box, you will need regulatory approvals. The reason so many things use external power supplies these days is so that the device manufacturer doesn't need to worry about UL or similar regulations - the power supply manufacturer takes care of that.

  • 1
    \$\begingroup\$ Thanks for the reply. I only took it apart because it didn't fit in the box. My problem is that I need 2 plugs (2 devices to be plugged in: pi and monitor-like device which has its own brick) and am trying to do it so that there is only 1 cord that needs to be plugged into the wall. Any suggestions on where to look to find what those regulatory requirements would be? \$\endgroup\$
    – canterman
    Dec 9, 2013 at 21:31
  • 1
    \$\begingroup\$ Generally, you'll want to avoid having to get a regulatory approval, as it has a significant upfront cost. If you want to have the standard, normally you'd have to buy it from UL/IEC. Though you may find some (older) copy with google, just on a FYI-basis: search for UL 60950-1 2007. Looking at older, dodgy copies is okay to get a glimpse of about what's inside. If you really decide to do it the harder way (the regulatory path), then you'll want to go and subscribe at UL/IEC for the latest standard. \$\endgroup\$ Dec 10, 2013 at 1:17
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    \$\begingroup\$ Building your product in such a way that all components (power strip, AC/DC adapter) directly in touch with the lethal voltages are complete (therefore already UL-approved) equipments from other manufacturers in an unmodified condition, used as intended, might be enough to avoid having to get a regulatory approval for the end product. \$\endgroup\$ Dec 10, 2013 at 1:29

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