Hello and welcome back to teckhme. In this article, we will see the float switch connection diagram and wiring. This circuit can be used to automatically fill the water tank. The float switch is basically a combination of NO and NC circuits, and the change of its contacts depends on the alignment of its placement.
Float switch
The float switch used in this circuit has three terminals in total. The black line is a normal line, the blue line is NC (normally closed), and the red line is NO (normally open). When the float switch is aligned from top to bottom as shown in the figure below, the blue is NC and the red is NO. But when the float switch is aligned from bottom to top, blue becomes NO and red becomes NC. Therefore, the float switch used for water filling is generally connected to the common terminal and the NC terminal. So under normal conditions, the motor will turn on, and when the water tank is full, the motor will turn off.
Float switch wiring diagram
Look at the wiring diagram of the float switch.
Here you can see that we can turn on the motor manually or run in automatic mode. When the selective switch is positioned to manual mode the contactor will turn on and the motor also be turned on and it will run until we manually turned off. Turn on when the water level becomes low. Once water is added, the motor will automatically shut down.
how to connect the circuit:
1. Connect the four-pole MCB as the input control as shown in the figure above.
2. Connect all three connections to the input terminals of the contactor. As shown in the figure above, connect the motor terminals to the output terminal of the thermal overload relay.
3. Connect the A1 terminal of the contactor to the "1" terminal of the selector switch.
4. As shown in the figure above, connect the A2 terminal of the selector switch to'R' through the normally closed contact of OLR.
5. Connect the common terminal of the float switch to the A2 terminal of the selector switch, and connect the NC terminal of the float switch to the A1 terminal of the selector switch.
6. As shown in the figure above, connect the red indicator light to the "R" phase through the normally open contact of the contactor. So when the contactor is turned on, the red light will also turn on.
7. As shown in the figure above, connect the green indicator light to the "R" phase through the normally closed contact of the contactor.
8. As shown in the figure above, connect the yellow indicator light through the normally open contact of the thermal overload relay.