Could anyone give advice on hooking up a SPD switch to a 120 V

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Could anyone give advice on hooking up a SPD switch to a 120 V power supply?I have a power supply that is on whenever you apply power to it and wanted to hook up a switch like so. Is that the safest way to do it? I will shrink wrap the extra leg of the SPDT switch not in use. Thanks!

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You should buy a power entry module that connects to a standard PC cable. These power entry modules can have an optional fuse tray for overcurrent protection. To answer your question, switching the live line is all you need, but some power entry modules switch both live and neutral. If you have a spdt, you might as will switch both. It protects you just in case your supply is miswired

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Looks good.

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Hi Eric, Yes, I do have that power entry module with the fuse that you mention. How can I switch both the line and the neutral with one switch if there are only 3 posts?

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If its a spdt it has a common and 2 contacts that are N.O. or N.C depending on position. If you hook up Neutral (Return) you will short from L-N or you will open your return when you close the Common to L depending on where you wire your Line Voltage.

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I think the NEC advises against putting a switch on Neutral in 120V

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Oh crap @Stephen_Jensen is right. I had a brain fart. For some reason I read spdt as dpst. A spdt should only be tired to the live. The input should be connected to common and the output to n.o. if your power entry only has 3 tabs… Honestly, I’d ring it out with a multimeter. I’d figure that those 3 tabs would be live, neutral, and ground, but I don’t know if just live is switched our both live and neutral.

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I would just use a single pole single throw to avoid confusion

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That is how older PC’s used to be wired. The line in should go to one of the throw terminals, and the common terminal to the PSU.

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Switching one side (L only) if fine as long as your supply feed is not faulty (as in bad Neutral wiring between you wall socket and street supply). FYI - there is no circuit until there is a connected loop with no breaks from L to N (like a switch in off position) See pic https://docs.google.com/drawings/d/1OIlLBjNxEiPdli5x82xaVbwuticX-PF-izQD_WO6-dg/edit?usp=sharing

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DPST

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Thanks for the great responses everyone!