Liquid level sensor is using infrared optical principle, the detection of liquid level, liquid level signal through the optical transmission, conversion to electrical signals for output, voltage signal collected by the sensor for level discrimination, the sensor has the advantages of compact design, small volume, waterproof, cylindrical shape square and drilling installation; installation mode diversification can be superimposed. Under the device, lateral and oblique to the installation, sensor head smooth, easy to clean, and the accuracy is better to the float type liquid level switch, controllable accuracy within 0.5mm, and existing float type liquid level switch accuracy is + 3.0mm; ray principle, no friction mechanical moving parts and greatly increased the life;

TECHNICAL PARAMETERS:

Working voltage: DC5V[special requirements can be changed to 12V/24V]
Working current: <10MA
Output mode: analog output 0-4.5V
Output mode two: high / low level signal output
Response time: <500ms
Insulation resistance: 100M
Working temperature: -30~80
Working humidity: 0-100%RH
Waterproof characteristics: all sealed waterproof design
Installation: M15*12 round hole
Lead length: 0.5 meters [default]
Weight: 30g
Size: 30mm*20mm*12mm

APPLICATION RANGE:

Water dispenser, water purifier, air conditioning fan, humidifier, air conditioning fan, steam class and other electrical products that require water level control and protection, as well as industrial field control level detection;

Design considerations:
Liquid level sensor acquisition circuit design, circuit and software control should pay attention to,

the use of liquid level switch is not simple to use high and low potential to judge. For example: the MCU I/O port, voltage greater than 0.7VDD is reliable is that high voltage potential, I/O port that is less than 0.3VDD only reliable low potential voltage between 0.3VDD and 0.7VDD is high or low is uncertain. So we have to use the A/D port to achieve the normal operation of the level switch. After sampling the voltage data, the data is analyzed. Every 0 seconds sampling time, 10 consecutive sampling voltage is greater than 0.15V, that is not water, 10 consecutive sampling voltage is less than 0.15V, it is a water, this way can solve the steam environment, at the same time scale of the problem is resolved; at the same time and we must remember: the tail of the level switch must be dry, do not allow the steam channeling to switch inside, otherwise it will fail. To use waterproof type.

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