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Comment by zaabis | Hacker News Reader

Can you elaborate?

For starters, 240VAC input represented by what appears to be a vanilla barrel jack; PCB relay module that doesn't look like it'd come close to meeting clearance, creepage, etc requirements expected of such applications; wiring represented as discrete point-to-point while completely ignoring the importance of gauge, insulation rating, etc. I just hope an ignorant passerby doesn't try to hack this up with speaker wire and arbitrary AliExpress relay module thinking the relays are rated for 240VAC so it must be OK (when everything else wasn't designed for such high voltage application).

The motor shown also appears to be a NEMA17 stepper motor...

All valid points, the beauty of Github is that you can write a pull request and add all those informations to the project, or even better, you can write what an alternative solution would be 'Instead of using X, you can use Y'. If you feel extreme generous you could even use this as a teaching opportunity. Explain concept like Creepage starting from the existing example and propose the alternative solution from there.

A courtesy HN response and 3 self-service pointers is the limit of my generosity...for everything else, find a charity.

A PR would be great actually. Open source projects are amazing and more people can use it safe. Or you can share here the improvements and will modify it myself.

It's a Fritzing diagram, which is to say it's a schematic, not a layout. So the thickness of lines should not be taken as indicative of any physical properties like connector style, wire gauge, or insulation. Clearance and creepage are concerns for PCB designers, but there doesn't seem to be any custom PCB layout and design work here - why mention it?

Check the todo to start:

> Add laser beam switches with reflector (stops & reverses the door when interrupted, for safety reasons)

Garage doors also have torque limits. If there’s an obstruction (such as a person) the door stops or reverses direction.

The UI is built with that in mind.

- User has to keep pressing UP/DOWN buttons in order the door to work. - If connection is lost door stops. - If there are both actions door stops. - If there are hardware actions and phone actions door stops.

The beams are also considered as a feature.

Since it’s WLAN the door can operated outside line of sight. Door should reverse, otherwise someone could get pinned.

I don’t have small children so I’m not personally worried, but I do question if the deviation from standard automatic door UX is a good decision.

This definitely seems like one of those situations where following what the industry has been doing with regards to system behaviors is the best way to go.

Garage door manufacturers have probably seen it all at this point, and I imagine just about every behavior has a tragic story (and probably a big lawsuit) behind its being implemented.

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