I have a project to open and close a high voltage circuit (e.g. 240 V) with a relay using low power, let's say 5 V.
Is it possible that I can use it as a switch to on or off the circuit without providing it power (5 V) continuously to close the circuit?
I want to make an electric switch for 240 V which just takes 5 V for an instant to switch only. For example, if I have a 5 V battery I don't want it to drain continuously.
I want to make it like a toggle switch.
Or there are any other options I can use?
Best Answer
Figure 1. A bistable relay. Note that A3 is common. Pulse A1 to switch one way and A2 to switch the other. The relay will remain in its last state.
Figure 2. A self-locking 12V single bistable relay module.
You might consider getting one with a second changeover contact. You can use this to monitor the switching action and switch off the changeover pulse when the changeover is detected.
Always keep your mains wiring well away from and routed separately from the low-voltage control wiring.