Modular Water Supply Quality Monitor

A new water quality monitor that incorporates sensor modules, previously unavailable from HORIBA.

The Modular Water Supply Quality Monitor GX-100 is capable of measuring seven essential parameters that need to be controlled under drinking water regulations: turbidity, color, pH, conductivity, free residual chlorine, water pressure, and water temperature.

*¹GX:Global transformation(X)
*The sensor modules are the various modular measurement units equipped with sensors.
*Company names, product names, and service names mentioned on this page are trademarks or registered trademarks of their respective companies.


TURBCOLORFRCpHCONDWater PressureWater Temperature


*Turbidity, color, and free residual chlorine capable of automatic zero-calibration.

Easily detachable sensor module system

The sensor module can be easily attached and detached in simple steps! No special tools are required.

Easy operation with your device

The sensor module can communicate with a Windows® PC or tablet via USB.  Using the dedicated app, calibration can be performed from your office.

Significantly reduces on-site time

By having spare sensor modules ready, you only need to replace them with the maintained units on-site.


Interface Module: Displays measurement values.  Also possible to communicate with mobile devices and PCs.

Product nameModular Water Supply Quality Monitor
Measurement itemsTurbidity, color, free residual chlorine, water pressure, pH, conductivity, water temperature
(Flow rate can also be selected and displayed (reference value))
*The measurement subject is tap water whose measurement item values are within the ranges stipulated in the Japanese drinking water testing method.
Measurement methodRefer to Table 1
Measurement rangeRefer to Table 1
RepeatabilityRefer to Table 1
Display methodi)Display of each component by LCD on the interface module
ii)PC display and operation is also possible via USB connection (*)
iii)Display and operation on mobile devices is also possible via Bluetooth® connection (*)
*A dedicated app is required. Up to eight items (including flow rate) can be displayed simultaneously.
Calibration methodRefer to Table 1
Automatic zero calibration(Turbidity, color, free residual chlorine)
Calibration method: Filtered water sample
Calibration Start method: Calibration starts with an internal timer and Modbus® communication
Calibration period: 1 to 9999 hours (arbitrary setting)
Calibration time: 20 minutes
Automatic drainageStart method: Drainage starts with an internal timer and Modbus® communication
Drainage period: 1 to 9999 hours (arbitrary setting)
Drain count: 1 to 9 times (arbitrary setting)
Drain time: 9 to 45 minutes
Cleaning methodTurbidity, color: Continuous cleaning of cell window with wiper
Free residual chlorine: Continuous cleaning with beads
Sample water conditionsTemperature: 0 to 40℃ (should not be frozen)
Pressure: 0.1 to 0.75 MPa
Conductivity: 100 μS/cm or more
Amount introduced into the analysis section (flow rate): 80 to 100 mL/min
・When test-running, be sure to flush the instruments thoroughly before passing water through them.
・Be sure to provide a bypass for the piping leading to the instrument.
・If there is a risk of the sample water freezing, take measures by using insulation and heat retention device.
・Water samples measured with this device cannot be used for distribution.
・To keep the flow rate stable, avoid sudden fluctuations in water pressure.
CommunicationInterface: RS-485 communication (Modbus® protocol)
                Communication speed: 19200 bps
                *Can be changed (2400 bps to 230400 bps)
FunctionLiquid leak detection function
Data memory
(When SD card is inserted)
The measured values of the measurement items are stored in the SD card in the interface module.

Memory interval: 1 second, 1 minute, 1 hour (every hour on the hour)
Data memory time: 1 second intervals - approx. 99 days
                              1 minute intervals - approx. 99 days
                              1 hour interval - approx. 1 year
                              * The latest data will be stored in memory.
Wiring connection portWiring inlet (suitable cable: φ7.0 to 11.0 mm)
Pipe connection portSample water inlet: φ6/4 pipe
Drain: φ6/4 pipe
Air outlet: φ6/4 pipe
Sample water outlet: φ6/4 pipe
StructureMeasurement unit: Indoor installation type
Exterior case material: ABS, SUS304
Interface module: Indoor/outdoor installation type (IP65 equivalent)
Exterior case material: AES
Main material of liquid contact partsPMMA, PEEK, PPS, ABS, PVC, PVDF, FKM, EPDM, glass, ceramic, SUS304, C3604, PET, FEP
Power supplyDC 24 V ±10%
Power consumption75 W
MassMeasurement unit: Approx. 10 kg
Interface module: Approx. 1kg
External dimensionsMeasurement section: 480(W) x 166(D) x 323(H)
Interface module: 155(W) x 119(D) x 155(H) (unit: mm)
Installation temperature conditionsAmbient temperature: 0 to 40°C
Installation humidity conditionsAmbient humidity: 85% or less (no condensation)
Installation environment conditions・A flat, stable location with little vibration or shock
・The atmosphere must not contain dust, mist, corrosive gases, etc.
・Atmospheric pressure
・A place not exposed to direct sunlight (measurement unit)
・A well-ventilated area
・Altitude below 2000m

● Table1 Measurement item specifications

Measurement itemMeasurement methodMeasurement rangeRepeatabilityCalibration method
Turbidity90° scattered light method0.00 to 10.00 NTU/degree±2.5% of full scalePolystyrene latex standard solution
Formazin standard solution
ColorTransmitted light absorbance method0.0 to 20.0 PtCo/TCU/degree±5.0% of full scaleColor standard solution
Free Residual ChlorinePolarographic method0.00 to 5.00 mg/L±2.5% of full scaleDPD colorimetric method
Water TemperatureThermistor method0.0 to 50.0 °C±0.5 °CStandard thermometer
pHGlass electrode methodpH 0.00 to 14.00±0.1 pHpH standard solution (NIST standard/USA standard)
ConductivityAC 2 electrode method0 to 5000 μS/cm
0.0 to 500.0 mS/m
±2.0% of full scaleKCl standard solution
Water PressureSemiconductor detection method0.000 to 1.000 MPa
0 to 10 bar
±1.0% of full scaleReference pressure gauge

* The flow rate can also be displayed as a reference value.

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