Applications
- Drinking water
- Municipal wastewater
- Industrial wastewater discharge limit monitoring or process optimization
- Food and beverage
- Power and semiconductors
- Reverse osmosis (RO) process

Description
Chlorine is measured using the DPD colorimetric method (US EPA 4500-CI G and ISO 7393-2 accepted method). The determination ranges of the analyzer vary from trace μg/L to 200 mg/L Cl2 using the (optional) internal dilution module.
Method
Chlorine-containing samples are reacted with N,N-diethyl-p-phenylenediamine sulfate in the presence of a suitable buffer. The indicator and buffer are added and react with chlorine to produce a pink color. This compound is measured at 525 nanometers.
Features
Measured parameter | Cl2 | ||||||
Range
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Reproducibility*
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Limit of detection | 0.01 ppm |
Wavelength | 525 nm | ||||
Demineralized water | Not required | ||||
Reference | UNI ISO 7393-2:2018 | ||||
Number of reagents | 2 | ||||
Min. analysis time | 6 minutes | ||||
Default analysis time | 15 minutes | ||||
Reagent consumption**
|
Reagents and standards
Chlorine-containing samples are reacted with N, N-diethyl-p-phenylenediamine sulfate in the presence of a suitable buffer. The indicator and buffer are added and react with chlorine to produce a pink color. This compound is measured at 525 nanometers. In total chlorine and monochloramine measurements, potassium iodide is added.
Features
Measured parameter | Cl2 | ||||||
Range
|
|||||||
Reproducibility*
|
|||||||
Limit of detection | 0.01 ppm |
Wavelength | 525 nm | ||||
Demineralized water | Not required | ||||
Number of reagents | 3 | ||||
Min. analysis time | 6 minutes | ||||
Default analysis time | 15 minutes | ||||
Reagent consumption**
|
Reagents and standards
Chlorine-containing samples are reacted with N, N-diethyl-p-phenylenediamine sulfate in the presence of a suitable buffer. The indicator and buffer are added and react with chlorine to produce a pink color. This compound is measured at 525 nanometers. In total chlorine and monochloramine measurements, potassium iodide is added.
Features
Measured parameter | Cl2 | ||
Range
|
Wavelength | 525 nm | ||||
Demineralized water | Not required | ||||
Number of reagents | 3 | ||||
Min. analysis time | 6 minutes | ||||
Default analysis time | 15 minutes | ||||
Reagent consumption**
|
Reagents and standards
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) |