• Drinking water
  • Iron removal processes and residual coagulant monitoring
  • Industrial wastewater
  • Measurement of effluents and wastewaters
  • Boiler feed water
  • Corrosion control
  • Cooling water
  • Surface water


Iron is ubiquitous on Earh's crust, it can be found in varying amounts in surface waters. It can can also be found in potable water especially when used as coagulant in water purification processes.
The determination ranges of the iron analyzer vary from trace μg/L to 200 mg/L using the (optional) internal dilution module. Ranges also depend on the chemical method used.


In an acid buffered solution, ferrozine and iron react to form a purple colored complex measured at 572 nm. The absorption intensity is proportional to the iron concentration in the sample.

In a slightly acidic buffered solution, 1,10-phenanthroline and ferrous ion react to form an orange color in proportion to the iron concentration. The Fe(II)-phenanthroline complex is quite stable and measured at 430 nm. The absorption intensity is proportional to the iron concentration in the sample. A reduction of Iron(III) to Iron (II) must first be carried out in order to measure both iron species.


(Ø 26 mm)
3 ppm
(Ø 16 mm)
7 ppm
(with dilution)
200 ppm
Wavelength 430 nm
Number of reagents 2
Min. analysis time 8 minutes

Technical Specifications

Model 3S-CL
Sampling Mode Batch, with freely settable frequency.
Sample Pressure: Atmospheric
Temperature: 5 ‐ 45°C (41 ‐ 113°F)
Flow Rate: 80 to 500 mL/min
Connection: 6 mm (¼-in.)
Drain Pressure-free drain
Connection: 12 mm (½-in.)
Input Streams 2
Material Epoxy-coated stainless steel AISI 304
Dimensions (H x W x D) 604 x 380 x 210 mm (23.6 x 14.8 x 8.2 in)
Weight 20 kg (44 lbs)
Power Supply Input Voltage: 115 VAC,230 VAC,24 VDC
Power consumption: max. 80 W
Output signals 2 x 4-20 mA analog outputs
Modbus via RS485,Ethernet
Alarms 2 SPDT programmable voltage-free relays
Digital Input None, Online, Start Extra, Skip Idle, Emergency Stop
Ambient Temperature 5 - 45 °C (41 - 113 °F)
Ambient Humidity 10 - 90 % RH (non-condensing)
Protection Grade IP54 (indoor only, outdoor use possible with external cabinet, not included)