DULCOTEST® Chlorite Sensors

Chlorite Measurement

ProMinent enables online measurement of the Chlorite concentration in water. Chlorite can be generated as a by-product to water treatment with Chlorine dioxide. In many countries, it is subject to monitoring duty e.g. in municipal water works.
For this reason, Chlorite must be analyzed as a matter of routine. As determination methods so far, only laboratory methods such as ion chromatography have been considered. Beside high investment and operation costs, these methods are very supervision intensive and time intensive due to the necessary sample handling and require a high education level of the operators. The biggest advantage, however, is that the determination value is only available hours or even days after sample taking and thus reactive measures for process optimization are not possible at all or only possible with delay. Therefore, we offer the first worldwide first online measuring station for Chlorite.

Application Areas

  • Drinking water generation using Chlorine dioxide
  • Disinfection with Chlorine dioxide in food and beverage industries

Our program offers the following advantages:

  • Clearly increased process safety and automation of the measurement
  • Cost-savings for investment and operation through simple installation and less labor utilization
  • Exact and reliable real-time measurement
  • Use of sensor technology with presence of Chlorine dioxide, Chlorine and Chlorate without cross sensitivities
  • Easy modular process integration of all sensors required for the entire solution via suitable fittings
  • Calibration with a method optimized by ProMinent (DPD)
  • Control devices with staged capacities adjusted to the requirements
  • Also available as panel-mounted complete measuring station, adjusted to the special requirements in waterworks and easy to commission as plug & play module.


Our DULCOTEST® product family of Chlorite Sensors includes two versions with different measuring ranges for a solution to your specific measurement needs.


  • No cross-sensitivities with presence of Chlorine dioxide, Chlorine and Chlorate
  • High sensitivity for trace-measurements in waterworks up to 0.5 ppm (Type CLT 1-mA-0.5 ppm)
  • Higher measuring range dynamic up to 2 ppm for other applications in combination with Chlorine dioxide treatment and especially for Quality Control of Chlorine dioxide generators (Type CLT 1-mA-2 ppm)
  • More efficient process control through precise amperometric real-time measurement (short response times)
  • No disturbance by clouding or coloration thanks to amperometric measuring principle
  • No drifts thanks to stable zero point
  • No disturbance through temperature influence due to integrated temperature compensation
  • Reduced dependence on flow and cross sensitivities thanks to diaphragm covered electrodes
  • Fast commissioning through short starting times
  • Long lifetime thanks to diaphragm-separated electrodes from process surroundings as well as defined electrochemical conditions by electrolyte
  • Easy and cost-efficient maintenance through diaphragm cap changing
  • Multiple connection possibilities to periphery: via two conductor cable to 4-20 mA interface of DULCOMETER® D1C controllers; to the DULCOMETER® DMT measurement transducer for forwarding the signal to a programmable logic controller (PLC) or SCADA system, or integration in Bus systems (PROFIBUS®, CANopen Bus)
  • Short delivery times enable expedient replacement
  • Special parameters and private labeling for OEM partners
  • For detailed information on the sensors please see download section.




DGMa modular in-line sensor housing

Features Advantages and benefits  
  • Modular design for up to five (more on request) sensors of any type (PG 13.5 and/or R 1" thread)
  • Cost effective and simple upgrading/retrofitting through variable modules
  • Enhanced measuring and process safety by means of the flow monitor module
  • Resistant to electrical interference through a potential equalizer pin
  • Simple assembly (pre-mounted on panel)
  • Simple and quick installation
  • Quick response time of the measurement because of low volume capacity

DLG III in-line sensor housing

Features Advantages and benefits  
Multiple Sensor housing for
  • Simple cleaning of the sensor housing and sensor by means of a removable housing cup
  • Cup can be used as container for a calibration solution
  • two sensors (pH, redox, conductivitiy, temperature, fluoride) with thread PG 13.5 plus
  • Enhanced measuring- and process safety as housing is resistant to electrical interference due to a potential equalizer pin
  • one sensor (chlorine, bromine, chlorine dioxide, ozone) with thread R 1" (25mm)
  • Simple and quick installation
  • Quick response time of the measurement because of low volume capacity


Portable Measuring Devices


Microprocessor-controlled Photometer for calibrating amperometric and fluoride measuring systems. Photometers are pre-assigned to defined verification procedures and include various measurements. (...more)



Multi-Parameter Controller diaLog DACa

The diaLog DACa controller uses intelligent controller functions to close the control circuit between ProMinent DULCOTEST® sensors and ProMinent® metering pumps. (...more)


Measuring and control device DULCOMETER® Compact

The new measuring and control device DULCOMETER® Compact for pH and redox measured variables is equipped with the standard functions for use in water treatment plants, allowing the operator to switch between the measured variables pH and redox, and between P and PID control characteristics. (...more)


Single-Channel Measuring and Control Instrument DULCOMETER® Type D1Cb/ D1Cc

The DULCOMETER® Type D1Cb is suitable for applications in drinking water, wastewater and cooling water treatment. The single-channel measuring and control unit D1Cb is equipped for all-important measured variables for basic applications in water treatment and with an error and calibration log book (...more)


Cut Sheet: Chlorine Analyzer Packages | Part #: 7750243 | Updated: 12/12/16
Cut Sheet: Dulcotest Sensors | Part #: 7750241 | Updated: 4/13/16
Cut Sheet: Dulcotest Sensors | Part #: 7750241 | Updated: 4/13/16

Catalog Section

Catalog: Dulcotest Sensors Catalog Section | Part #: xxxxxx | Updated: 12/5/16
Dulcometer Controllers: DACa Controller | Part #: xxxxxx | Updated: 8/5/13

Instructional Videos

Video: D1Ca | Part #: xxxxxx | Updated: 4/23/13
Video: DACa Controller - Part 1 - Overview (WEBINAR) | Part #: xxxxxx | Updated: 8/7/13
Video: DACa Controller - Part 2 - Identity Code (WEBINAR) | Part #: xxxxxx | Updated: 8/14/13
Video: DACa Controller - Part 3 - Controller Comparison (WEBINAR) | Part #: xxxxxx | Updated: 8/21/13
Video: DACa Controller - Part 4 - Live Demo (WEBINAR) | Part #: xxxxxx | Updated: 8/28/13
Video: DT1 - 4 Photometric Test Kits | Part #: xxxxxx | Updated: 7/11/14
Video: Setting Up A New DACa Controller (WEBINAR) | Part #: xxxxxx | Updated: 12/13/13

Manuals And Instructions

Manual: D1C Setting Record | Part #: 987205 | Updated: 7/1/05
Manual: D1Cb & D1Cc O&M | Part #: 986362 | Updated: 9/1/11
Manual: D1Cb/D1Cc | Part #: 986362 | Updated: 9/11/14
Manual: D2C Part 1: French & English | Part #: 987613 | Updated: 12/1/08
Manual: D2C Part 2 Chlorine | Part #: 986846 | Updated: 12/1/08
Manual: D2C Part 2 PH/Chlorine | Part #: 987855 | Updated: 7/19/13
Manual: D2C Part 2 PH/Chlorine Dioxide | Part #: 986736 | Updated: 1/6/14
Manual: D2C Part 2 PH/ORP | Part #: 987822 | Updated: 10/1/08
Manual: D2C Part 2 PH/pH | Part #: 987661 | Updated: 1/7/14
Manual: D2C Settings Deocumentation | Part #: 987279 | Updated: 4/3/14
Manual: DACa Controller O&M | Part #: 985250 | Updated: 4/1/14
Manual: DACa Controller O&M Supplementary Instructions: Web Interface/LAN | Part #: 983683 | Updated: 1/28/16
Manual: Fluoride Panel English | Part #: 987315 | Updated: 10/1/08
Manual: Part 2: Adjustment & Operation Bromine | Part #: 987353 | Updated: 2/1/07
Manual: Part 2: Adjustment & Operation Chlorine | Part #: 987905 | Updated: 3/1/09
Manual: Part 2: Adjustment & Operation Chlorine Dioxide | Part #: 981734 | Updated: 6/1/07
Manual: Part 2: Adjustment & Operation Chlorite | Part #: 987028 | Updated: 3/5/14
Manual: Part 2: Adjustment & Operation Conductivity Conductive | Part #: 987926 | Updated: 4/1/08
Manual: Part 2: Adjustment & Operation Fluoride | Part #: 987306 | Updated: 5/1/07
Manual: Part 2: Adjustment & Operation H2O2 Peracetic Acid (PAA) | Part #: 987936 | Updated: 12/1/08
Manual: Part 2: Adjustment & Operation H2O2 Peri (Peroxide) | Part #: 986847 | Updated: 11/1/07
Manual: Part 2: Adjustment & Operation Inductive Conductivity | Part #: 986954 | Updated: 10/1/08
Manual: Part 2: Adjustment & Operation Oxygen | Part #: 987139 | Updated: 7/1/07
Manual: Part 2: Adjustment & Operation Ozone | Part #: 987698 | Updated: 12/1/07
Manual: Part 2: Adjustment & Operation PAA | Part #: 986976 | Updated: 3/9/14
Manual: Part 2: Adjustment & Operation PH | Part #: 987907 | Updated: 3/1/07
Manual: Part 2: Adjustment & Operation Redox/ORP | Part #: 987850 | Updated: 10/1/10
Manual: Part 2: Adjustment & Operation Standard Signal | Part #: 987528 | Updated: 4/1/07
Manual: Part 2: Adjustment & Operation Temperature | Part #: 981809 | Updated: 4/1/07
Manual: Pause Normal Hold Function | Part #: - | Updated: Unknown

Quickstart Guide

Quickstart Guide: Calculating PID Values For D1C Cl | Part #: None | Updated: Unknown
Quickstart Guide: Calculating PID Values For D1C PH | Part #: None | Updated: Unknown
Quickstart Guide: Calculating PID Values For D1C Redox | Part #: None | Updated: Unknown
Quickstart Guide: Calculating Proportional Values For Cl | Part #: None | Updated: Unknown
Quickstart Guide: CDN CLE Quick Start | Part #: None | Updated: Unknown
Quickstart Guide: CDN CTE Quick Start | Part #: None | Updated: Unknown
Quickstart Guide: D1C PH Calibration Quick Start | Part #: None | Updated: Unknown
Quickstart Guide: ORP Quick Start | Part #: 7750088 | Updated: Unknown

Sensor Manuals And Instructions

Data Sheet: Data Sheet PH Senosr With Vario Pin Head | Part #: 987501 | Updated: 5/1/00
Data Sheet: Data Sheet Vario Pin Connections | Part #: 987625 | Updated: 9/1/99
Parts List: DGMa Manual Parts List From July 03 | Part #: 987356 | Updated: 10/1/11
Sensor Manual: BRE 1 And 2 MA Sensors | Part #: 987341 | Updated: 8/6/14
Sensor Manual: CDE 2 And 3 MA Sensors | Part #: 986656 | Updated: 8/1/08
Sensor Manual: CGE2 MA And 4P Sensors | Part #: 987354 | Updated: 9/1/07
Sensor Manual: CLE 3 1 Manual | Part #: 987320 | Updated: 2/1/09
Sensor Manual: CLE CTE CGE CAN Sensors Supplement | Part #: XXXXXX | Updated: 11/4/14
Sensor Manual: CLT 1 Manual | Part #: 987069 | Updated: 10/1/09
Sensor Manual: CTE 1 MA And DMT Sensors | Part #: 987371 | Updated: 12/1/09
Sensor Manual: CTE 1 Short Manual | Part #: 987690 | Updated: 2/1/99
Sensor Manual: Data Sheet LFT 1 FE | Part #: 987884 | Updated: 4/1/99
Sensor Manual: Data Sheet Pt 1000 SE | Part #: 986685 | Updated: 5/6/14
Sensor Manual: DO 1 And 2 Sensors | Part #: 987199 | Updated: 1/4/14
Sensor Manual: Fluoride Sensor | Part #: 986544 | Updated: 6/8/14
Sensor Manual: Fluoride Transducer | Part #: 987342 | Updated: 8/3/14
Sensor Manual: ICT 2 Conductivity Sensor | Part #: 986948 | Updated: 12/1/10
Sensor Manual: ICT IMA Conductivity Sensor | Part #: 986949 | Updated: 7/4/14
Sensor Manual: ICT1 Conductivity Sensor | Part #: 986955 | Updated: 12/1/09
Sensor Manual: LF Conductivity Sensor | Part #: 987823 | Updated: 9/6/14
Sensor Manual: Measuring Transducer 4-20mA FP V/1 FP 100 V1 | Part #: 986545 | Updated: 7/8/14
Sensor Manual: OZE 3 MA And OZE 2 4P Manual | Part #: 981815 | Updated: 7/1/96
Sensor Manual: PAA 1 Sensor | Part #: 986961 | Updated: 10/1/08
Sensor Manual: PER 1 Sensor | Part #: 986884 | Updated: 12/1/09
Sensor Manual: PH ORP Temp Transducer 4L | Part #: 987467 | Updated: 12/1/00

Frequently Asked Questions

Standard Lead Times for Products / Expediting

Standard lead times are listed below. If you need an order expedited, please contact your customer service representative. Please be aware that overnight shipments receive priority over ground shipments. Gala/Beta/Concept - 3 days Sigma series - 5 days ProMus - 2 weeks Dulcometer 3-4 days

When discharging to atmosphere, what steps will improve repeatability of dosing?

Installing a spring in the discharge valve of the pump gives some improvement, but for the maximum improvement, a backpressure valve should be installed at the end of the line.

What variables can be measured or controlled with ProMinent equipment?

We can measure or control pH, Redox, Free or Total Chlorine, Chlorine Dioxide, Conductivity, Ozone, Peracetic Acid, Hydrogen Peroxide and Dissolved Oxygen.

Can you explain what the different options are using the Ident-code for the D1C controller?

The Identcode for a D1C has 13 parameters that can be specified. The first parameter is the type of mounting such as wall or panel mount. Then the operating Voltage must be selected. The measured variable is the parameter being measured such as pH, chlorine, Redox ? The next selection is the connection of measured variable, which selects how the sensor is wired, such as an SN6 connector. The correction variable selects whether there is pH or temperature correction. The next variable is feed forward capability. This signal can be used for metering proportional to the flow rate. The control input allows control by contact closure. The signal output function can be set up as measured, controlled or correction variable. The power control variable pertains to the alarm functions and how and what they control. The pump control option is set up for whether pumps will be controlled. The control characteristic sets the pump up for proportional control band or the more sophisticated PID control. The interface is not used at this time. The last variable allows for the selection of the language.

When programming the D1C, what options can I enable or disable?

The D1C controller can be set up for a complete operating menu or a reduced menu. The reduced operating menu permits operation of the most important parameters, but will not allow the operator to change system parameters that are normally set up once, during initial installation. The complete operating menu allows all parameters to be changed.

What is feed forward control?

This signal can be used for metering proportional to the flow rate.

What option is required on controllers when you want to connect to a chart recorder?

The controller must have the signal output option for measured value for recording or two mA outputs.

What do I need to order with a D1C?


What do I need to order with a D2C?


I am working with a ProMinent D1C controller and controlling pH. I keep getting a check sensor error. What is causing this problem?

The problem may be that the checkout time is set too low. This feature is used to detect a defective sensor: if the value is set to 1 second, the processor looks for changes on the sensor readings; if the display does not change during this interval, a check sensor will result. This feature can be set from 1 to 9999 seconds or turned off in the measure value mode of the controller. Turn the checkout time to off or set the measured time to at least 60 seconds, so the sensor is checked once a minute instead of once every second.

Where are conductivity controllers most commonly used?

Conductivity controllers are used in industries including, paper, pharmaceutical, plating, electronics, breweries, power production, and plating. Two very popular applications are bottle washing and cooling towers.