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LDO fluorescence dissolved oxygen meter

It is used for monitoring dissolved oxygen in sewage treatment plant biochemical pond; surface water monitoring.
● Water and sewage treatment Wastewater treatment plant aeration tank, power plant water treatment ● Water environment monitoring rivers, lakes, seawater, etc. ● Aquaculture industry aquaculture ● Other food industry, chemical industry

The fluorescence method for dissolved oxygen measurement is based on the principle of fluorescence quenching. The blue light irradiates the fluorescent material to excite the fluorescent material and emit red light. Since the oxygen molecules can take away energy (quenching effect), the time and intensity of the excited red light are inversely proportional to the concentration of oxygen molecules. By measuring the phase difference between the excitation red light and the reference light, and comparing with the internal calibration value, the concentration of oxygen molecules can be calculated.

● Innovative principle of fluorescence method, no need to change the diaphragm and electrolyte, basically maintenance-free;
● No oxygen consumption, no flow rate and agitation requirements, and no cross-interference from the following materials: H2S, pH, Co2 +, NH4 +, SO42-, Cl-, Cl2, etc .;
● Digital sensor with strong anti-interference ability and stability, the sensor cable length can reach hundreds of meters;
● Plug and play sensors, automatic identification, support dual-channel input;
● The instrument can provide isolated RS232 digital interface and isolated RS485 digital interface, and supports standard Modbus ASCII and Modbus RTU protocols;
● Support Chinese and English languages;
● Programmable relay output: Any relay can be set to high alarm, low alarm, and timer modes;
● With the function of automatic saving of historical data, it can store and query historical data information for 10 years.

Measurement performance <br /> Range: 0.00 ~ 20.00mg / L or 0.00 ~ 20.00ppm, air saturation 0 ~ 200%
Resolution: 0.01mg / L, 0.01ppm
Accuracy: ± 1% or ± 0.15mg / L, whichever has the largest absolute value sensitivity: ± 0.05mg / L
Response time: 90% <30 seconds; 95% <90 seconds (at 20 ℃)
Temperature compensation: NTC10KΩ automatic temperature compensation calibration: factory calibration, one year without calibration, field calibration display: LCD liquid crystal display date, time, measured value, historical trend line, etc. Chinese and English operation menu optional data storage: automatic storage function, Power-off data protection, can store and query 10-year historical data on-site setting: completed by the transmitter button

Output <br /> Analog output: isolated 0/4 ~ 20mA, maximum load 750Ω, fault current output current optional relay output: 3 programmable relays, which can be set as alarm function and timing function Relay capacity: 2A, 250VAC
Digital interface: MODBUS RS232 / RS485, Profibus DP optional

Power supply <br /> AC power supply: 85 ~ 265VAC, 50Hz / 60Hz
DC power supply: 24VDC ± 10%

Physical properties <br /> Transmitter size: 270 × 205 × 100mm
Sensor size: Φ45 × 118mm
Material: Transmitter: PC + ABS Sensor: 316L stainless steel Connection: 1 inch tapered male thread

Environmental performance <br /> Protection level: Transmitter: IP65 Sensor: IP68
Working temperature: Transmitter: -20 ℃ ~ 60 ℃ Sensor: 0 ℃ ~ 60 ℃
Relative humidity: 0 ~ 95%, non-condensing working pressure: maximum 7.5Bar