chlorophyll sensor

one.Working principle of chlorophyll sensor

chlorophyll sensor detected the fluorescence of chlorophyll and estimated the concentration of phytoplankton, which provides a high-performance measurement of chlorophyll A.The chlorophyll sensor is a device specially used to detect chlorophyll content.Its working principle is based on the fluorescence and light absorption properties of chlorophyll.

When illuminated by natural light or a light source of a specific wavelength, chlorophyll absorbs light energy and emits fluorescence.The intensity of this fluorescence is proportional to the chlorophyll content, so the chlorophyll content can be estimated by detecting the intensity of the fluorescence.

The advantage of chlorophyll sensor is that it can measure chlorophyll content in real-time, quickly and non-destructively, and can be used for research, investigation and monitoring of rivers, lakes, ponds, marine surveys, aquaculture, drinking water sources, algae and phytoplankton conditions.

two.chlorophyll sensor technical parameters

Measurement principle	Fluorescence method
Measuring range	0-400ug/L
resolution	0.01ug/L
Accuracy	R2>0.999
temperature compensation	Automatic temperature compensation
Self-cleaning function	Equipped with an automatic cleaner to prevent biological adhesion and light window pollution to ensure long-term monitoring stability; the automatic cleaning time and cleaning frequency can be set, and the power consumption is 0.7W
Output mode	RS-485 (ModbusRTU protocol)
Storage temperature	-5℃~65℃
working environment	0℃~50℃,<0.2MPa
Installation method	Submersible installation, 3/4NPT mounting thread
Cable length	5m
Power consumption	0.4W,12V power supply
powered by	DC: 12V～24V
Protection level	IP68
Calibration method	Two point calibration
Shell material	316L stainless steel

three.chlorophyll sensor size/installation

1.chlorophyll sensor size chart

2.Wiring diagram

The cable is a 4-core shielded wire:

Red wire—power wire (12~24V) black wire—ground wire (GND)

Green line—485B Yellow line—485A

3.Installation

1) On site, according to the actual situation, you can choose 6 points (3/4 NPT) thread for fixed installation or

Mounting accessory bracket installation, or other installation method that can fix the sensor.

2) Fixed installation is preferred, drag chain installation is prohibited.

3) Full consideration should be given to water flow and liquid level changes during installation to ensure that the water flow can cross the optical path and the sensor is 10cm or deeper underwater.

4) Installation distance requirements: keep more than 3cm from the side wall and more than 10cm from the bottom.

Four.chlorophyll sensor maintenance and care

1.Maintenance schedule

Maintenance project maintenance time notes

Clean the sensor 0.5 to 3 days (without brush) 4 to 8 weeks (with brush)

Sensor inspection 6 months

Replace O-rings every 1 to 2 years

2.Maintenance methods

1) Check the outer surface of the sensor.Rinse the outer surface of the sensor with clean water.If there is still dirt remaining, please wipe it with a damp soft cloth.For some stubborn dirt, you can add some household detergent to the water to clean it.

2) Check the sensor cable and check whether the cable sheath is broken.The cable should not be tight during normal operation.

3) Check the measurement window to see if there is any dirt and wipe it with a dust-free cloth.

4) Sensor calibration can be calibrated through the host computer software, or it can be calibrated by yourself.

RS-485 sends MODBUS commands to self-calibrate.

3.Sensor calibration

3.1 Zero point calibration

Use a brown beaker to measure an appropriate amount of distilled water, place the sensor vertically in the solution, with the front end of the sensor at least 10cm away from the bottom of the beaker, and wait for 3 to 5 minutes for the value to stabilize before performing zero point calibration.

3.2 Slope calibration

Place the sensor in the standard solution, with the front end of the sensor at least 10cm away from the bottom of the beaker, and wait for 3 to 5 minutes for the value to stabilize before performing slope calibration.

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