I've designed a simple switch/timer circuit for the following environment:

  • Residential installation for North America (technically only for Canada)
  • Single-phase 120Vac
  • Current of switched output device not to exceed 10A, typically <1A
  • Power dissipation of circuit itself is negligible (<<1W)
  • Circuit's power supply is an enclosed class-II isolated unit and meets UL60950-1
  • Circuit detects mains voltage through an optoisolator rated to 5kV
  • Output relay is an enclosed class F-insulated unit
  • Essentially one-off installation, not mass market production

As an absolute beginner in the area of electrical safety standards, where on the internet should I go to seek information on:

  • Whether this is UL/CSA-certifiable, and how I would go about doing that
  • Which safety standards apply
  • Detailed technical information on applicable safety requirements

I've already checked what I think is the authoritative source, but it seems to be behind a paywall. The same goes for UL standards such as 60950.

  • \$\begingroup\$ I am more familiar with UL than CSA, but I believe they are similar in a lot of respects as are the US and Canadian electrical codes. UL has a system for authorizing shops that build one-off equipment to apply the UL label without having each item evaluated by UL. In some situations, a local building inspector may accept the installation of something that does not have a label. You can probably do anything you want for your own use at your own risk. You pretty much need to use labeled equipment if it is accessible to the public or even used without your personal supervision. \$\endgroup\$ – Charles Cowie Oct 7 '18 at 19:11
  • \$\begingroup\$ Your next step is to contact UL or CSA and make sure of the validity of your analysis - the excuse "Well that's what it said on the internet" as your defence in court probably gets you 5 years... \$\endgroup\$ – Solar Mike Oct 7 '18 at 19:24
  • \$\begingroup\$ Standards are really intended to be used by professionals. I think the price is reasonable for people use them in the course of their work. My employer purchased what was needed where I worked. Universities and technical schools may make copies available to students. \$\endgroup\$ – Charles Cowie Oct 7 '18 at 19:29

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