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I am designing a mains powered device which has two general purpose mains output sockets, both switched by relays. I am trying to find out the wiring rules specifically for the US, but also for EU and AU. How can I find out which certifications the device will fall under (for electrical safety)?

Specifically: Does this device require double pole relays? Is there freely available information which may answer these questions? Also wondering does the design require fuses or a circuit breaker?

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    \$\begingroup\$ I don't know about certifications, but at least you can guess some scenatios if they are good or bad. Like what happens if you have a single pole relay and it only cuts the neutral wire. In addition, what if the wall socket is ungrounded and the device has grounded plug? Your device should not allow dangerous scenarios. \$\endgroup\$
    – Justme
    Nov 21 '20 at 9:21
  • \$\begingroup\$ Research extension cables with multiple outlet sockets. \$\endgroup\$
    – Andy aka
    Nov 21 '20 at 10:04
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    \$\begingroup\$ Much of the EU uses 2.5 A Europlugs or 16 A Schuko plugs, sometimes known as type C or F respectively, neither of which are polarised. So you'll need to use double-pole relays to safely switch your outlets there. \$\endgroup\$
    – Graham Nye
    Nov 21 '20 at 10:23
  • \$\begingroup\$ @Justme luckily AU and US have polarised plugs in code at least. If your wiring is ungrounded and without an earth current detector, you need to go home and try again \$\endgroup\$
    – Bringle
    Nov 25 '20 at 11:27
  • \$\begingroup\$ @Bringle I was just trying to explain in general how things are and what you have to deal with when making a global product. You cannot assume you have polarized plugs even if your country has those, and you cannot assume your device is only used in new buildings with earthed sockets, as old buildings with two prong sockects exist in all countries. \$\endgroup\$
    – Justme
    Nov 25 '20 at 11:43
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Is there freely available information which may answer these questions?

In the US, the answer is no. Some of the applicable codes and standards are not easy to obtain without purchasing them.

The National Electrical Code, NFPA 70 (NEC) is published and offered for sale by the National Fire Protection Association. It can be read online, but not downloaded. It is available to be borrowed in many public libraries.

The NEC is the basis for all local wiring regulations. Each individual locality has its own rules. Those rules mostly cover only permits, inspection, enforcement etc. but some add or delete details with respect to NEC. Those rules are often freely available online and some provide downloadable versions of NEC.

Electrical devices are generally required to conform to applicable standards. Those standards are generally published by Underwriters Laboratories (UL). UL standards are offered for sale and not widely available otherwise. Electrical devices are generally required to be "listed" and "labelled" as meeting applicable standards. Listing must be done by and labelling authorized by a nationally recognized testing laboratory (NRTL) as determined by OSHA.

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  • \$\begingroup\$ Thank you, some digging ahead \$\endgroup\$
    – Bringle
    Nov 25 '20 at 11:29

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