Relay with self-interrupting second relay
Now we have expanded our self-interrupter circuit with a second relay. If the button is pressed, the rst relais is activated closes it contacts and therefore activates the 2nd relais. This 2nd relais as activated toggles the contacts and turns off the power of the rst relais. This deactivates the 2nd relais, which turns on again the rst relais and so on. To check the functionality, you can hear a hum of both relays, as well as the lighting of the control LEDs. The process repeats, until the push button is released.