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can I activate a 24v relay using my house's power grid(220v)? Answered

I am making an automatic  fish feeder and to activate it ? I'm thinking about using a 24v 1100ohm relay that I have laying around. My question is: can I do it? If not can I just put a resistor on it? It's supposed to be activeted a bout 15 minutes every day.


The safest way would to use a 24 volt plug pack, I'm not sure if this is the answer your looking for but why not use a cheap timer and plug pack?


I'd already decided to use the timer, but I still need to activate the relay. I know that the safest way is to buy a wall tranformer, but I am trying to make this as cheap as I can, so can or can't I activate the relay with 220v?

Bearing in mind that you render the relay "unsafe" by doing so, yes, you can do this "online", you need a 10K, 5W dropper resistor, and a series diode to put DC into your relay coil;

I also found some old PCB mounted transformers, and I found the one that was powering the relay, but I don't know which pins are the input and the output. Can you help me?

The transformer is likely got a part number on it somewhere. just google "data sheet your part number" and if your in luck you should get a PDF with everything you need to know about your transformer.

The heavier wires are likely to be the secondary, the lighter, the primary.