NO2-
Applications
- Drinking water
- Process optimisation of wastewater treatment plants
- Industrial and municipal wastewater
- Mineral water monitoring
- Surface water

Description
The 3S colorimeter is a compact analytical instrumentation for online analysis and process monitoring. The colorimeter is based on a color-developing chemical reaction carried out inside the analyzer's glass cell. The sample, coming from an external reservoir or process stream is autonomously grabbed by the instrument and mixed with the appropriate reagents to make the reaction happen. The analyzer uses an LED light source and a photodiode to photometrically measure the developed color intensity (absorbance). The absorbance is proportional to the concentration of the target chemical species (analite).
Features:
- Low reagents consumption and analytical reliability thanks to our custom designed miniature peristaltic pumps
- Dual compartment design to guarantee a complete separation between the electronics and the hydraulic section
- Color touchscreen to show the last measured value clearly, and to set all the options and settings via an user friendly interface
- Datalogger function with data history in graphical form and USB download
- Automatic calibration, validation and cleaning to reduce down time and operator intervention, their frequency can be freely set by the user
- Fully integrable in industrial automation via the analog outputs (2 x 4-20 mA channels), digital output (2 relays + ModbusRTU) and digital input (voltage free contact)
The determination ranges of the nitrite analyzer vary from trace μg/L to 125 mg/L NO2 using the (optional) internal dilution module. The result can be expressed as NO2 or N-NO2.
Method
In acidic media, nitrites react with sulfanilamide and N-(1-naphthyl)-ethylene diammonium dichloride, forming a purple colored dye. The absorbance intensity is proportional to the nitrites concentration in the sample and is determined at 525 nm.
Reagents
Standard solutions
Features
Range (Ø 26 mm) |
500 ppb N-NO2 (1.6 ppm NO2) |
Range (Ø 16 mm) |
1 ppm N-NO2 / (3.2 ppm NO2) |
Range (with dilution) |
40 ppm N-NO2 / 125 ppm NO2 |
Wavelength | 525 nm |
Number of reagents | 2 |
Min. analysis time | 6 minutes |
Technical Specifications
Model | 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 |
Cabinet Material | Epoxy-coated stainless steel AISI 304 |
Dimensions (H x W x D) | 604 x 380 x 242 mm (23.6 x 14.8 x 9.4 in) |
Weight | 20 kg (44 lbs) |
Power Supply |
Input Voltage:115 - 240 VAC 50/60 Hz or 24 VDC (optional) Power consumption: max. 80 W |
Output signals |
2 x 4-20 mA analog outputs Modbus RTU via RS485 |
Alarms | 2 SPDT programmable voltage-free relays |
Digital Input | Online,Start Extra,Skip Idle,Emergency Stop |
Ambient Temperature | 5 - 45 °C (41 - 113 °F) |
Ambient Humidity | 10 to 90 % RH (indoor use only, outdoor installation possible with protective cabinet or shelter not included) |
Protection Grade | IP54 |
Documentation
- 🇺🇸 / 🇬🇧 Nitrite Colorimeter Datasheet
- 🇮🇹 Nitriti Datasheet Colorimetro
- 🇺🇸 / 🇬🇧 3S-CL-1.0 User Manual
- 🇮🇹 3S-CL-1.0 – Manuale Utente
- 🇺🇸 / 🇬🇧 3S-CL-2.0 – User Manual