I have to design a circuit where a momentary switch is used to control the main power of board. Since its a momentary switch I have a requirement of latching relay. Using only one switch I have control turn On and turn Off of the board. Once press the switch and release switch, power is On and it remains in the ON state as long as switch is is pressed once again. I press it again the power should turn OFF. Hence I understood that I should use latching relay in my design. I have selected 1937650-9 from TE. Can someone please explain me the working of this. If i consider this relay my design will look something like attached image. Im still not sure whether this relay would fulfill my requirement. How would the relay get to know that in first press of switch, the set coil has to energize and output should be latched. And when I press the same switch for second time, the reset coil will energize. Can someone please explain me how the selected relay works. Or the relay that I have selected is not a correct one for my requirement. If its not a suitable one for my requirement can someone suggest a alternate relay..
The datasheet shows that the 1937650-9 is a 24 V, bistable 2-coil relay.
Table 1. The datasheet shows that the 2-coil relay has a common + terminal (A3) and that to operate the relay you connect A2 to '-' and to reset it you connect A1 to '-'.
Figure 1. How the bistable 2-coil relay is intended to be operated.
You can't do what you want with one relay and a push-button unless you use the impulse relay I showed you in your previous question, How to select a relay for main power input.
Figure 2. The pawl mechanism is advanced on every impulse of the relay coil. Image source: HomoFaciens.