DULCOTEST® Dissolved Oxygen Sensors

Dissolved Oxygen Measurement

The measurement of "Dissolved Oxygen" indicates the amount of gaseous oxygen physically in water in units of mg/L (ppm). ProMinent offers two different sensor types for the online measurement of this parameter.

Application Areas

  • Effluent treatment: optimization of the oxygen entry into the activated sludge tank (biological step) of purification generators.
  • Fish farming: Control of the oxygen in waters that must be conditioned for the breeding of production animals.
  • Drinking water supply: Optimization of the aeration step in water works
  • Environmental technology: Assessment of the quality of surface waters

Our program offers the following advantages:

  • Design, measuring ranges and process connections that are tailor-made for different applications
  • The sensor type DO2 is generally designed for the use in purification systems, such as activated sludge pools, which require a self-cleaning sensor
  • The sensor type DO1 is bar-shaped, and can thus be easily installed in standard dip pipes for applications not requiring self-cleaning
  • Use of the sensor technology with water varying in quality (pH, salt content, temperature, pollution tolerance).
  • Direct connection of the sensors to a programmable logic controller (PLC) (electroplated calibrated 4-20mA-signal) or as a stand-alone solution with ProMinent's D1C controller
  • Controller (type: D1C) with staged capacities adjusted to the respective requirements and with input possibilities for all correction sizes to increase the measurement accuracy
  • Easy calibration with air or alternatively via reference measurement
  • For frequently arising applications, complete standardized measuring point as plug & play modules with precise, internally adjusted components.


Our product family DULCOTEST® Sensors for Dissolved Oxygen offers two sensor series in various designs and measuring ranges for the solution of your measuring task.

Sensor types

  • Type DO1: bar-shaped sensor for simple installation in standard dip pipes in various applications e.g. fish farming, waterworks, and environmental control. Measuring range 0-20 mg/L
  • Type DO2: Self-cleaning swimming bowl, especially for the control of oxygen input in the activated sludge tanks of purification generators. Measuring range 0-10 mg/L


  • Efficient process guidance through precise amperometric real-time measurement
  • No disturbance through clouding or coloration thanks to amperometric measuring principle
  • Pollution insensitive PTFE diaphragm
  • Stable zero point thanks to diaphragm-covered extensive electrodes
  • No disturbance through temperature-influence thanks to integrated temperature compensation (Pt 1000)
  • Reduced dependence on flow and cross sensitivities through diaphragm-covered electrodes
  • Automatic diaphragm rupture signaling
  • Direct connection to programmable logic controller (PLC) through electrically isolated, calibrated and temperature-compensated 4-20 mA signal
  • Fast commissioning through short starting time
  • Long lifetime thanks to diaphragm-separated electrodes from process surroundings as well as defined electrochemical conditions through electrolyte
  • Easy and cost-efficient regeneration of sensor through replacement of sensor element via bayonet catch (every 2 to 3 years)
  • Short delivery times enable near-term replacement




Housing for Sensor Type DO 1

Features Advantages and benefits  

For the installation in a standard dip pipe, 2" PVC or similar (DN 50) (provided by customer): To be installed in with the dip pipe adapter available as an accessory (#10200537)

Variable process integration for applications in fish farming, waterworks, environmental control, etc.
For the installation in a standard dip pipe, 2" PVC or similar (DN 50) (provided by customer): To be installed in with the dip pipe adapter available as an accessory (#10200537)

Sensor Housing for Sensor Type DO 2

Features Advantages and benefits  
  • The swimming bowl is fixed to a standard 2" PVC or Steel  (DN 50) pipe (provided by customer) and installed on the rails of the clarifier by means of the provided rail bracket and pipe adapter.
  • Tailor-made process connection for the application: oxygen entry into the activated sludge tank of a purification generator.
  • Self-purification of the sensors with permanent approach flow via venturi grooves on the bottom of the swimming bowl


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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.