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ring my bell? Answered

I have a switch and when it is opened I want to activate a bell for a second or two. I don’t want the bell to go off again until after the switch has closed and opened again.  What would be a good solution to this?  I’m guessing some kind of relay board but not sure where to look for this.  My bell is 120vac and switch is low voltage DC.


Here's a relay circuit, it needs two low voltage relays, ONE of them needs to have 120V rated contacts.

You could do some of this with electronics, but this is simpler.

Bell dinger.jpg

would you mind breaking it down for me? I can handle the wiring but reading schematics not so good. :-) Thanks!

How do you mean "break it down" ?

There's a battery or powersupply connected to a low voltage relay, via a switch. The switch is normally CLOSED. The relay is on.
In that position the relay contacts above it should be wired so that R feeds a current into C, a 1000uF capacitor, which stores electricity.

When the button is pressed the first relay contacts OPEN, and the capacitor discharges into the coil of the second relay, which closes and goes "dink".

While the button is held, nothing happens. When the button is released, and depending on how much R you use, it takes a few seconds for the capacitor to recharge for another "dink".

You need a timer set for one or two seconds that is activated on switch open.