Electronic – Soldering wires directly to male AC prongs

acpower supplysoldering

I am making a project that will fit into a 3D printed enclosure. I want to keep the project neat so I will have just one extension cord running from the wall (120VAC) into the enclosure to power all of my electronics. One of my devices requires 12VDC so in order to save space inside my constrained enclosure, I thought that I could solder wires directly to the AC input prongs of the power supply and heat shrink & electrical tape over that. The reason for not directly plugging it into the female end of the single extension cord entering the enclosure is that I need two additional items to be plugged into the cord that I was going to use wire nuts for. This 12VDC adapter will be powering 1A for only a few minutes at a time, maybe once per day.

Is it safe to solder the wires to the AC input prongs of the 12VDC supply?

Solder connection

Best Answer

Use a supply intended to be wired to

As you can tell, "wall warts" are not intended to have chassis wiring hooked up to their inputs. An easier and safer approach, provided you have the small amount of additional chassis space (3" by 2" by 1.1" for the Mean Well linked below vs. 2.8" by 1.9" by 1.25" or so for a wall wart) and the ability to bring a ground conductor (3 prong cord) into what you're building, would be to use a chassis mount enclosed supply, such as the Mean Well RM-15-12 (which is under $8 in onesies via Mouser). These supplies have screw terminal inputs that are intended to be chassis wired to and screw holes for mounting screws so they can be attached solidly to the case instead of flapping around in the breeze like your wall-wart would.

representative image of chassis mount supply