I would like to use a reed switch to control a solid state relay. Could I use the supply power for the control aswell? Thanks for your help.


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    \$\begingroup\$ Welcome to the site. Your question is to try trying to gain people's interest but they have to follow links and open separate documents. Please edit your question to add the part number of the device and the diagram from its datasheet, so that your question outlines everything in the one place. The better the quality of your question, the better the quality of the answers you will attract. Again, a warm welcome to the site. \$\endgroup\$
    – TonyM
    Apr 2 '20 at 6:07
  • \$\begingroup\$ I don't know of a mains powered SSR. Those I've seen are DC and opto-isolated. Lacking a reference for a mains powered SSR, I'd recommend considering the purchase of a HLK-PM01 or similar and using that with your reed switch and a common SSR. \$\endgroup\$
    – jonk
    Apr 2 '20 at 6:25

You cannot use the 240V to supply the control coil of the relay as you show in the picture. To me is difficult to understand really what are your specs, the driving coil changes with the power rating of the relay. Can you provide more specs?

To get a DC voltage to supply the coil one of the cheapest solution is similar to RC voltage divider https://www.microchip.com/forums/m/tm.aspx?m=841330&p=2

  • \$\begingroup\$ yes, a non-isolating dropper could work here, but don';t forget that you need reinforced insulation on the reed switch and its wiring as it must now be treated as live. \$\endgroup\$
    – Jasen
    Apr 2 '20 at 7:00
  • \$\begingroup\$ @Jasen yes you are right, I haven't mention this thanks :) \$\endgroup\$
    – tinix84
    Apr 2 '20 at 7:39
  • \$\begingroup\$ Hi Thanks for your answer, the kind of SSR is in the link below. I am trying to avoid adding a 12vdc to my project. temperatureshop.com.au/Solid-State-Relays/TCSSRA2510 \$\endgroup\$
    – JoshC
    Apr 2 '20 at 8:52

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