Power supply, power off relay, rc snubber

Hello! I'm using LED PS 12v 360W for diy 3d printer project. My idea is to use relay to switch on/off printer before/after print etc but im having problem with relay(arduino simple one) staying on forever,probably contact get welded from high inrush current. I got similar arduino relay but SSR type which have inbuild inrush protection (Non-repetitive peak surge 30 A datasheet) and 2A load current. About PS, i dont have precise specification but from searching online similar models, it says input load ~1.6A, inrush curent ~40A which is out of spec for my SSR relay. Now question about rc snubber, what would be values of R and C for this PS? Can i use one from dead PC PSU (wired on input connector)? Any suggestion? Thx in forward

So solution to this problem will probably be big ssr like "Fotek SSR-40DA" as rc snubb is out of my knowledge.

A RC snubber won't reduce inrush current. The usual way to reduce inrush current is to use a NTC thermistor designed for this purpose in series with the mains feed to the PSU. Some PSUs have one built in. If necessary you can add an external one. Here are some examples [www.digikey.com].

That said, a good SSR should be able to handle 40A inrush current. For example, the Crydom D2425 25A SSR is rated at 239A single cycle surge.

Beware of Fotek SSRs sold on eBay. Many of them are fakes.

Edited 1 time(s). Last edit at 07/17/2024 02:16AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Tnx. Will try that way with NTC and regular relay (cheap arduino type)