ISE combination sensor for ammonium and nitrate - WTW

ISE combination sensor for ammonium and nitrate - WTW

  • SKU: 107066
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  • Description

    Digital ISE sensor for NH4 and NO3, connectable to the IQ SENSOR NET

    Ion selective measurement of ammonium and nitrate free of reagents with automatic compensation of potassium/chloride with the VARiON® Plus 700 IQ:

    • Ammonium and nitrate measurement directly in the process
    • Simultaneous compensation of potassium, chloride
    • No sampling, reagent-free
    • Calibration free, long-term stability

    These especially stable electrodes ensure long operation times and a simple cleaning method. To measure, simply install the respective electrode into the IQ SENSOR NET, everything else will take place automatically. In the measured value display, the values that have already been compensated, are displayed, you can select potassium or chloride output. These values also stand for the signal output per 0/4-20 mA output or digital output (Profibus, Modbus RTU, Ethernet/IP, Modbus TCP) is directly available.

    New: Measurement of media with high ammonium load

    When thickening or dehydrating wastewater treatment sludge, the so-called centrate water is generated. This water has an especially high amonium content. The centrate water is not drained but rerouted into the wastewater circuit of the system or directly broken down into elementary nitrogen (deammonification). In both cases, the determination of the NH4 freight is very important for an optimal process run. High NH4 concentrations of up to 2000 mg/l can now be determined directly in the medium by means of the Varion®Plus 700 IQ, in centrate water as well as in process waters!

  • Specifications

    Ammonium Measurement

    Nitrate Measurement

    Measuring method


    Maximum Configuration

    Common reference electrode, two measuring electrodes, one compensation electrode

    Integrable Electrodes:

    Reference Electrode

    VARiON®Plus Ref

    Measuring Electrode

    VARiON®Plus NH4

    VARiON®Plus NO3

    Compensation Electrode

    VARiON®Plus K

    VARiON®Plus Cl

    Measuring range/ Resolution

    NH4-N: 1 ... 2,000 mg/l / 1 mg/l;
    0.1 ... 100 mg/l / 0,1 mg/l

    NH4+: 1 ... 2,580 mg/l / 1 mg/l;
    0.1 ... 129.0 mg/l / 0,1 mg/l

    NO3-N: 1 … 1,000 mg/l / 1 mg/l;
    0.1 ... 100 mg/l / 0,1 mg/l

    NO3-: 5 … 4500 mg/l / 1 mg/l;
    0.5 ... 450.0 mg/l / 0,1 mg/l

    Compensation Ranges

    K+: 0.1 ... 1,000 mg/l / 0.1 mg/l

    Cl-: 0.1 ... 1,000 mg/l / 0.1 mg/l

    Measuring Accuracy in laboratory standard solutions

    ± 5 % of measured value ± 0.2 mg/l in standard solutions

    Calibration Procedures

    Matrix adjustment against any reference value, 2-point-calibration possible with multiple standard solution

    Working Life (typically)

    Reference electrode: 18 months,
    measuring and compensation electrode: 18 months (in typical application - municipal sewage plants)

    Temperature Measurement and Compensation

    Integrated NTC thermistor,

    Range 32 °F … 104 °F (0 °C … +40 °C), Accuracy ±0.5 K, Resolution 0.1 K, t95 < 20 s

    Pressure Resistance

    Maximum 0.2 bar (incl. SACIQ sensor connection cable, with installed electrodes)

    Ambient Conditions

    Operating temperature: 32 °F … 104 °F (0 °C … +40 °C), storing temperature: 32 °F … 104 °F (0 °C … +40 °C)

    Electrical connections

    2-wire shield cable with quick fastener to sensor


    EN 61326, Class B, FCC Class A;
    Intended for indispensable operation




    Sensor body: V4A stainless steel 1.4571 Protective cup: POM
    Temperature sensor: V4A stainless steel 1.4571 Protection rating: IP 68 (0.2 bar, with installed electrodes)
    Electrode connector: POM


    Approx. 1.48 lb (670 g, without electrode, without sensor connection cable)


    VARiON®Plus 700 IQ: 2 years
    Electrodes: 1 year for defects of quality