Driving 24VDC DIN bistable (impulse) relay by Arduino

B

Baterka

When I was doing reconstruction of electrical network in my appartement, I did it with possible future home automation in mind. Because of that, all my lights are driven by DIN impulse (bistable) relays from EATON. They are driven by 24VDC from DIN switching power supply.

I started with development of a board with Arduino Nano that would act as a "smart switch" and will be sending same 24VDC impulses to the relays as when I hit real switch on the wall.

My question is, what should I use as a switching component? I totally ditched use of a normal relay as I think thats not needed for 24VDC and around 7W of power that the DIN relay needs to flip the state. I was looking into SSR relays, but I think that because it is DC, I can go just with normal MOSFET? Is that feasable? I was thinking about something like IRLML6344 as it is logic gate mosfet and 30V/5A seems enough.

  • Not sure if I can drive it directly from GPIO or I need e.g. resistor in front of the MOSFET?
  • Also, my concern is the possible inductance kickback from the relay. Is that a thing in this type of DIN relays?
  • One more concern is about shared ground reference. Is it ok for the Arduino board to share ground with the relay's power supply? Even if they will be two different DIN rail power supplies?
 

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