I salvaged an emi filter at some point

… and while i was foraging through my stores of e-waste i happened upon it(pictured). i wasn’t at all sure what it was but it looked like i might be able to integrate it into the PSU i’m building for my MPCNC so I did some googling. From what i read in the search results, and in one of ryan’s posts here – this isn’t particularly a necessity unless you start to see (and/or hear) some key issues; but my power supply is already built with several redundancies and “unnecessary” features so i guess my question is would there be any cons to having it installed? It has its own separate fuse in place so at the very least it’s a safety net for the rest of the machine right?

Emi is a very device-specific thing and although universal filters do exist I don’t think it would be very useful in this case. It would go between grid and the PSU, meaning that it would protect the grid from the psu and vice versa. I’d say the the issues would probably rather come from having stepper wires too close to some signal wires (usb, limits etc.) Or othetwise long and unshielded cables that would result in “intermachine” issues - mainly the spindle or a any control relay inductive spikes connecting to those wires.

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thank you for your insight, I doubt my machine will have any of those issues so perhaps it’s best the tri-mag stays on the bench for this one.