INSTRAN Total Hardness Analyzer from Spain is designed to handle all kind of samples ranging from drinking water to waste water application. It incorporates laboratory measuring technique (Colorimetric Titration) into online analyzer with self-cleaning in each analysis to ensure the measurement is in high precision.

The unique design of INSTRAN Total Hardness Analyzer with syringe volume-controlled method ensures syringe will never contact with samples or reagents and thus prolong the shelf life of the syringe. Also due to the accuracy of the syringe system, the volume of the drop is 0.015ml, which is a important point in the titration method where the titrant reagent is added drop by drop making the analyzer requires very little maintenance and low reagents consumption but yet powerful and high in accuracy.

INSTRAN Total Hardness Analyser

Measuring Principle: Colorimetric Titration

  • The Calcium complexes with the Erichrome Black-T to give a blue-violet colored complex.
  • This blue-violet colored complex, when titrated by the addition with the EDTA titrant, is broken up as the calcium EDTA complex which is more stable and when excess EDTA is present the Erichrome Black-T – EDTA complex is formed which is a rose colored complex.
  • Precise volume controlled of Sample, Reagent and Titrant reagents by syringe dispensing system ensure excellent accuracy and repeatability


  • Reliable, Exact and Fully Automatic Analysis Total Hardness
  • Self Cleaning After Each Measurement
  • Very low maintenance & operating cost
  • Low reagent consumption
  • Multi-Color Graphic Display


  • Drinking Water
  • Process Water
  • Waste Water Treatment Plant
  • Water Softening System Performance
  • Boiler and Cooling Tower Feed Water
  • Pool and Spa Water

Technical Specification

Measurement MethodColorimetric Titration Method
Measuring Range0 ~ 10, 0 ~ 20, 0 ~ 100, 0 ~ 200, 0 ~ 400 mg/L (ppm) as Total Hardness
Accuracy+/- 2 % FS + 0.02 mg/L (ppm)
Resolution0.02 mg/L (ppm)
Power100 ~ 240 VAC, 50/60Hz, 200 Watts Max
[Fuse Protection: 250V, 5A]
Dimension500 x 150 x 600 mm (L x W x H)
User InterfaceKeypads with 4 Keys and 4 Indication LED
DisplayBacklit, Graphic and Wide Screen Color
Output2 x Analogue Output 4 – 20mA, Max Load: 700 Ohms
2 x Digital Outputs
Input2 x Digital Inputs [Assigned to detect of lack of Sample or Reagents]
5 x Assignable Digital Inputs
CommunicationModbus RS485 (RTU / ASCII)
Relays4 x Assignable (Free Voltage) Relays with 3 Contacts (C, NO and NC)
CalibrationAutomatic with Schedule
Manual – Automatic On Demand
Sample Flow100 ml/min [Minimum]
WashingAutomatic after Each Measurement
[Programmable with Sample, DI Water or Washing Solution (Hard Cleaning]
Dispensing SystemSyringe Dispensing System with Fast Loop Sampling System [Prevent Syringe in contact with Sample or Reagents] made of Teflon
High reliability Solenoid Valve which can handle particles of dimension up to 1.5mm diameter
ReactorSmall Volume Reaction Cuvette [12ml to 17 ml] with Drain Solenoid Valve able
to handle particles, size up to 3mm diameter
Fluid SystemChemical Resistance Tubing made of Inert Material with direct connection
without coupling
Operating Temp-20 deg C ~ +65 deg C with Maximum RH at 95% Non-Condensing
Sample Temp+ 10 ~ 45 deg C
A I ANALYTICAL PTE LTD | Address 30, Kallang Place, #06-01, Singapore 339159 | Tel: +65 6459 0785 | Email: