Introduction

The online blue-green algae sensor uses the principle of fluorescence method, which is more efficient and faster than the traditional manua counting method, and can be monitored in real time online. The senso has better repeatability and stability. With automatic cleaning brush, it can eliminate air bubbles and reduce the impact of contamination on the measurement, make the maintenance cycle longer, and maintain excellen stability for long-term online use It can play an early warning role on algae reproduction.

Features

★ Digital sensor, RS-485 output, support MODBUS

★ With automatic cleaning brush to prevent contamination and eliminate air bubbles

★ Direct measurement, simpler than traditional manual counting method

★ Continuous online monitoring, real-time control of water quality dynamics

Technical parameter

Product name	Blue-green Algae Sensor
model	DS206
principle	Fluorescence method
Range	0-270, 000 cells/mL
Detection limit	300 cells/mL
Resolution	1 cells/mL
Linearity	R2>0.99
temperature range	0~ 50°C
Protection level	Ip68
Sensor interface	Support RS-485, MODBUS protocol
Installation	Input type,
Power information	DC 5~12V, current <50mA
size	Φ45*175.8mm
Probe cable length	10 meters (default), can be customized
Housing material	SS316
Self-cleaning system	Have

2,Preparation

• First take 0.1g of rhodamine B solution into 1000mL reagent bottle A, then add DI water or distilled water to 1000mL and shake well.
• Take 1mL of the above solution into 1000mL reagent bottle B, and then add DI water or distilled water to 1000mL and shake well. The solution concentration of reagent bottle B is 100 ppb.
• The prepared solution should be used within 24 hours.

3,Use

Rhodamine B shows that the fluorescence intensity is inversely proportional to temperature. Use 100 ppb rhodamine B standard solution. To properly set the sensor to ensure the sensitivity of algae blue-green algae at 20 ° C, enter the calibration value according to the temperature standard corresponding to the table below. (The table below shows algae blue-green algae as a function of temperature approximately equal to 100 ppb rhodamine B)

Temp, ℃	cells/ml
26	54600
27	52471
28	51376
29	49670
30	47641
31	45276
32	43258
33	40711
34	38905
35	37298
36	34875
37	33370

Note: The calibration using rhodamine B standard solution is only an approximate value. To ensure accurate readings, the fluorescence readings obtained on site must be linked to the results obtained from the extraction analysis of the above samples. Yushan used Rhodamine B (Item # 70301027) from Keystone.

Warning: Rhodamine B is listed as a substance that may cause carcinogenesis / induction of organism mutations. Gloves must be worn during operation.

Maintenance methods and common problems Maintenance schedule and method

I. Maintenance schedule

Online blue-green algae sensor with automatic cleaning brush can be automatically cleaned without frequent cleaning.

Maintenance task	Recommended maintenance frequency
Calibrate the sensor (if required by the competent authority)	According to the maintenance schedule required by the competent authority

2. Maintenance method Sensor maintenance

• External surface of the sensor: Clean the external surface of the sensor with tap water. If debris remains, wipe it with a moist soft cloth. For some stubborn dirt, you can add some household washing solution to the tap water to clean it.
• Check the cable of the sensor: the cable should not be tightened during normal work, otherwise the internal wires of the cable will be easily broken and the sensor will not work properly.

3) Check whether the measurement window of the sensor is dirty and whether the cleaning brush is normal.

• Check the sensor's cleaning brush for damage.
• 18 months of continuous use, need to return to the factory to replace the dynamic sealing device.

Frequently Asked Questions

Error	Possible reason	solution
The operation interface cannot be connected or the measurement result is not displayed.	Controller and cable connection error	Reconnect controller and cable
	Cable failure	Please contact us
The measured value is too high, too low or the value is continuously unstable	The sensor window is attached by a foreign object	Cleaning the sensor window surface
	Damaged sensor sponge	Replace the sensor sponge

Cable Definition

Power information

The power supply must be DC 5-12V +/-5%, current <50mA

Cable information

4 wire AWG-24 or AWG-26 shielding wire. OD=5mm

1, red line - power supply (VCC)

2, white line - 485 data _B (485_B) 3, green line --- 485 data _A (485_A) 4, black line --- ground (GND)

5, bare line shielding layer