I'm designing an electronics enclosure to be placed in series with the power cord for a device for control purposes and would like to know safest methods to do power breakouts within the plastic box. I'm planning on putting a power entry module on one end or possibly two to make the power breakout easier. I've seen terminal blocks but mostly used for DIN rails/control panels, not small enclosures. I only need 2 separate sets of hot/neutral/earth, one of which will be fed to a 5v power supply. I'd also like to know how to test wiring in something like this since I want to be sure the 120v lines are very secure and there's no potential for loose connections/soldering. There will be a relay switching 120v that goes out through another plug also, so don't know if that changes any protocol. Thanks

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    \$\begingroup\$ UL has a specification for strain reliefs, I think something like 35lbf (~155N) minimum pull-out strength. \$\endgroup\$ – Spehro Pefhany Aug 7 '20 at 14:20
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    \$\begingroup\$ Is this a hobby thing or are you designing a product that's gonna be marketed??? \$\endgroup\$ – Kyle B Aug 7 '20 at 14:32
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    \$\begingroup\$ Power cables with molded plugs on one side often have a molded flange on the other side which sits in a slot in the plastic box. For hobby use, I make liberal use of cable ties (including to hold the PCB). For making to sell, I guess, one might have to find a custom box manufacturer. \$\endgroup\$ – Indraneel Aug 7 '20 at 14:36
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    \$\begingroup\$ @KyleB this is for hobby only \$\endgroup\$ – coolro Aug 7 '20 at 14:38
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    \$\begingroup\$ @coolro For hobby, make a smallish hole in the box, put the mains cable in, then put a cable tie on it to stop it from slipping out. It will be as good as any cheap chinese stuff. Otherwise, you can design a strain relief on a piece of plastic or plywood and cable tie the plastic/plywood to the inside of the box. \$\endgroup\$ – Indraneel Aug 7 '20 at 14:42

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