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756 points mtlynch | 1 comments | | HN request time: 0s | source
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mtlynch ◴[] No.23927535[source]
Author here. Happy to answer any questions or take any feedback about this post.
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wojciii ◴[] No.23928108[source]
Cool project, but what about power management? What happens if the PC being controlled crashes and does not let you reboot it using keyboard shortcut?

I'm might be damaged by testing and working with embedded development.

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zyx321 ◴[] No.23928912[source]
If you need access to the power and reset, you can replace the respective buttons with a cheap relay switch controlled by GPIO. If you know what you're doing you can also solder your own circuit using opto-isolators instead of relays, to reduce the power draw on the Pi.
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hedora ◴[] No.23929195[source]
This isn’t a bad choice:

https://wiki.52pi.com/index.php/DockerPi_4_Channel_Relay_SKU...

It’s $17 for four relays, expandable to 16. If you wire it “normal closed” then the relays will only draw power while it’s resetting the other machine.

However, the relays are only rated for 3 amps. (360W at 120V). Also, the board is labeled backwards so, the NO port is normal closed, and NC is normal open.

Has anyone found something that’s similarly plug and play with a higher amperage rating?

Edit: this would work as a switched AC outlet (to replace a four outlet PDU) or for hot wiring the power / reset buttons. You could do both buttons and the AC line and have a relay left over.

I’d feel funny running AC that close to the lower button wires though (if cross those wires, it will certainly let the magic smoke out of your motherboard).

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1. zyx321 ◴[] No.23938543{3}[source]
It could work on a power line, but I'd seriously recommend against it for a beginner project. Anything over 50V requires proper safety procedures.