Waterline PO4-10/PO4-20 (Phosphate)


Process analyzers for Orthophosphate measurement

The WATERLINE PO4-10 and PO4-20 process photometers can be used for the monitoring and control of the concentration of orthophosphate (PO4 3-) in water. Measurement principle is the photometric detection of the color change of a water sample after the formation of a molybdoblue-phosphoric acid complex (PO4-10) or a molybdovanadate-phosphoric acid complex (PO4-20).

Main applications for the photometers are the monitoring of surface water, treated water, waste water or process water and the control of phosphate dosing plants. The analyzers consist of a control unit with touchscreen and an analysis unit with measuring chamber, valve, dosing pumps and all required tube connections. The control unit includes a microprocessor which controls the automatic measurement incl. sampling, rinsing, reagent dosing and surveillance of the photodetection system.

  • Automatic measurement incl. self-test and drift compensation
  • Easy operation via touchscreen
  • Adjustable limit value and alarm value
  • Programmable analog output (0/4-20 mA), optionally with USB port for easy data storage
  • Adjustable break time between two analysis
  • External start/stop of an analysis possible
  • No external calibration required
  • External plug connections (IP65) for alarm relay, limit relay, analysis relay, external start/stop, analog output 0/4-20 mA
  • Multi range power supply (110–230 Volt, 50–60 Hz)
  • Including polycarbonate wall cabinet
Parameter Orthophosphate (PO4 3-)
Description Automatic microprocessor controlled analyzer for the photometric determination of dissolved orthophosphate
Typical Applications Monitoring of surface, treated and clarified water Control of phosphate dosing plants
Analysis Method: Molybdoblue method Molybdovanadate method
Analyzer type WATERLINE PO4-10 WATERLINE PO4-20
Measuring Range 0,05 – 10 ppm 0,5 – 50 ppm
Resolution 0,01 ppm 0,1 ppm
Accuracy 2 % of end value
Reproducibility 1 % of end value
Zero-point Stability automatic adjustment
Number of Samples 1
Operating Pressure0,1 - 10 bar
Temperature5 - 30 °C
Sample Volume25 ml per analysis (excluding rinsing)
Sample Conditionclear, filtrated
Chemical DemandspH 4-8
Drainpressure free into open drain
Storage Temp.0 - 30°C0 - 30°C
Usage/analysisappr. 1,35 ml each reagentappr. 2,7 ml
Reagent volume500 ml500 ml
Suitable forappr. 370 analysisappr. 185 analysis
Cycle (approx.)3 - 12 min (incl. rinsing)
Sample interval 1 – 99 min or external start/stop