Teachers, I do not understand the level controller connected to the liquid level on the high, medium and low three lines is the use of what principle to send signals to the controller, ask you. Thank you!
Electrode level controller is the use of liquid conductive principle to control the liquid level. A low-voltage alternating current is applied to the electrodes. When the liquid is connected to the two electrodes, an electrical signal is detected in the controller, and then the control signal is output.
Circuit by detecting the three different values of the line voltage, or the size of the current flow can be judged by the level of water level
Level control relay connected to the liquid level of the sensor line principle:
Level relay is the control of the liquid level of the relay, the use of liquid conductivity, when the liquid reaches a certain height when the relay will action to cut off the power. When the liquid level is lower than a certain position, the power is turned on to make the pump work and reach the function of automatic control. Automatic control consists of sensors and control actuators. The liquid level controller's sensor is generally a wire. The use of water conductivity. Water conductivity is poor, can not directly drive the relay. So there must be electronic circuit to amplify the current to promote the relay work. High level for the water level overflow point, free control of water level, the water level to automatically stop; low line for the automatic water point, the water level at this point automatically start the water device; midline for the regular contact.
