Nutrients Analyzer
Nitrate Meter

SMR21 series

Nitrate Analyzer

Nitrate Analyzer is connected directly via RS485 communication interface, providing simple, reliable, cost-saving process data with remote monitoring, calibration, configuration and diagnostics capabilities. Nitrate Meter housing in a robust IP68 proof enclosure, 1500 N tensile strength Kevlar reinforced cable, up to 1.2 km digital data transmission, the NO3-N analyzer and NO3-N Meter is ideally used in water/wastewater industry.
View More Details
  • All-in-One Compact Housing, Built-in Transmitter and Sensors
  • Robust IP68 Water Submersible Protection
  • Plug & Play, On- line Realtime Measurement
  • Ultra Low Power Consumption, Ideal for Outdoor Applications
  • 1500 N Tensile Strength Kevlar Reinforced Cable
  • Surge Protection for Power and RS485 Communication
  • RS485 Digital Communication, Minimize Cabling and Engineering Cost
  • Standard Modbus RTU Protocol, Direct Connected with PLC, HMI
  • Software Tool for Data Monitoring, Calibration , Configuration and Diagnosis
  • Sapphire Glass Windows to Prevent Scratch
  • Innovative Nano Coating to Remain Window Clean
  • Auto Cleaning Wiper, Less Maintenance
  • Onboard Memory Allowing Users Easily Calibrate and Configure Sensor at Lab and Distribute to Various Fields Sites
  • Software Tool for Data Monitoring, Calibration , Configuration and Diagnosis
SMR21 Nitrate (NO3-N) Analyzer 
Type Optical
Measurement range SMR21-3: 0~10 mg/L (10 mm)
SMR21-4: 0~20 mg/L (5 mm)
SMR21-5: 0~50 mg/L (2 mm)
SMR21-6: 0~100 mg/L (1 mm)
Accuracy ±5% in standard solution
Resolution 0.01 mg/L
Repeatability ±3% in standard solution
Light Source Xenon flash lamp
Beam Angle 180°
Light Path Length 1, 2, 5 mm
Process flow rate Max. 3 m/s
Operating pressure Max. 10 Kgf/cm2
Operating Temperature 0~50 °C
Response time 10 secs
Protection IP68
Housing SS316L
Turbidity (or total suspended solids) measurement range SMR21-3: 0~250 NTU ( or 0~500 mg/L)
SMR21-4: 0~500 NTU ( or 0~1,000 mg/L)
SMR21-5: 0~1,000 NTU ( or 0~2,000 mg/L)
SMR21-6: 0~2,000 NTU ( or 0~5,000 mg/L)
Turbidity (or total suspended solids) Accuracy ±5% measured value
Resolution 0.01 mg/L
Repeatability ±3% in standard solution
Dimension Φ 75 x 416 mm
Weight approx. 5 Kg 
cable: 80 g/m
Typical Application
Drinking water, water treatment, wastewater, fishery
  • Output Signal: RS485 (Modbus RTU protocol), 19,200 bps, 8 data bits, no parity, 1 stop bit; 4~20 mA (optional)
  • Data Resolution: 16 bits (0.001% FS)
  • Surge Protection: 4000 V DC
  • Power: 12 V DC ±10%, 0.5 A
  • Protection: polarity, overload, short circuit
  • Safety: CE, FCC
Typical Applications
  • Drinking water, water treatment, wastewater, fishery
Measurement Method
  • The Xenon flash lamp emits UV-Vis light passing through the sample to be analysed. The spectrometer resolve the wavelength into high resolution spectrum with advanced algorithms to provide the concentration and eliminates mutual interferences such as chemicals, turbidity and color.
Standard cable length is 3 m, customized length is available upon request