Endress+Hauser COS61D Specifications

TI00387C/07/EN/14.18 71411045 2018-07-17

Products

Solutions Services

Technical Information

Oxymax COS61D/COS61

Measurement of dissolved oxygen

Digital optical sensor based on the principle of fluorescence quenching, with or without Memosens protocol

Application

• Wastewater treatment plants – Oxygen measurement and regulation in the activated sludge basin for a highly

efficient biological cleaning process

– Monitoring the oxygen content in the wastewater treatment plant outlet

• Water monitoring Oxygen measurement in rivers, lakes or seas as an indicator of the water quality

• Water treatment Oxygen measurement for status monitoring, e.g. of drinking water (oxygen enrichment, corrosion protection etc.)

• Fish farming Oxygen measurement and regulation for optimum living and growth conditions

Your benefits

• Optical technology: – Minimum maintenance – Maximum availability

• Sensor with digital signal processing: – Calibration data saved in sensor – High degree of EMC protection thanks to digital communication with the

transmitter

• Extended maintenance intervals and a high degree of longterm stability

• Intelligent self-monitoring guarantees reliable measured values

• No flow needed - measurement possible in still water

• COS61D - the Liquiline sensor – Plug&Play: Safe communication based on Memosens protocol – Optionally with M12 plug for fast connection to the transmitter

• COS61 - the Liquisys sensor – Compatible with tried-and-tested COS31 with COM2x3W: Easy measuring point

changeover to optical technology

– Compatible with COS41 with COM2x3D with conversion kit

Function and system design

Oxymax COS61D/COS61

Measuring principle

Sensor structure

Oxygen-sensitive molecules (markers) are integrated into an optically active layer (fluorescence layer). The fluorescence layer, an optical insulating layer and a cover layer are applied on top of one another on a carrier. The cover layer is in direct contact with the medium. The sensor optics are directed at the rear of the carrier and therefore at the fluorescence layer.

Measurement process (principle of quenching)

If the sensor is immersed in the medium, an equilibrium is very quickly established between the oxygen partial pressure in both the medium and the fluorescence layer.

1. The sensor optics send green light pulses to the fluorescence layer.

2. The markers "respond" (fluoresce) with red light pulses.  The duration and intensity of the response signals are directly dependent on the oxygen

contents and oxygen partial pressure.

If the medium is free from oxygen, the response signals are long and very intense.

Oxygen molecules mask the marker molecules. As a result, the response signals are shorter and less intense.

Measurement result

The sensor returns a signal that is proportional to the oxygen concentration in the medium.

‣

The medium temperature and air pressure are already taken into account to calculate the oxygen concentration in the sensor.

The sensor provides measured values for temperature and partial pressure as well as a raw measured value. This value corresponds to the fluorescence decay time and is approx. 20 μs in air and approx. 60 μs in oxygen-free media.

For optimum measurement results

1. During calibration, enter the current air pressure at the transmitter.

2. In the case of saline media: Enter the salinity.

3. For measurements in the units %Vol or %SAT: Also enter the current operating pressure in the measuring mode.

• Operating Instructions for Memosens, BA01245C For all transmitters, analyzers and samplers in the Liquiline CM44x/P/R, Liquiline System CA80XX and Liquistation CSFxx product families

• Operating Instructions for Liquisys COM2x3, BA00199C

2 Endress+Hauser

Oxymax COS61D/COS61

1 2

Measuring system

COS61D

A complete measuring system consists of the following components at least:

• Oxymax COS61D oxygen sensor

• Liquiline CM44x multi-channel transmitter

• Sensor cable, optionally available with M12 connector

• Assembly, e.g. flow assembly COA250, immersion assembly CYA112 or retractable assembly COA451

Optionally:

• Assembly holder Flexdip CYH112 for immersion operation

• Extension cable CYK11

• Cleaning system

 1 Example of a measuring system with COS61D

Sensor cable

Liquiline CM44x

Flexdip CYH112

A0012882

Basin rim with railing

Oxymax COS61D

FlexdipCYA112

Endress+Hauser 3

COS61

1 2

A complete measuring system comprises:

• Oxymax COS61 oxygen sensor

• Transmitter, e.g. Liquisys COM2x3-W

• Sensor cable

• Assembly, e.g. flow assembly COA250, immersion assembly CYA112 or retractable assembly COA451

Optionally:

• Flexdip CYH112 assembly holder for immersion operation

• VS junction box (for cable extension)

• Cleaning system

Oxymax COS61D/COS61

 2 Example of a measuring system with COS61

Liquisys COM253

Oxymax COS61

Pipe (ascending pipe)

Input

Measured values

Measuring ranges

Dissolved oxygen [mg/l, µg/l, ppm, ppb or %SAT or hPa]

Measuring ranges apply for 25 ˚C (77 ˚F) and 1013 hPa (15 psi)

With Liquiline CM44x, CM44xR, CM44P or with Liquisys COM2x3-W:

• 0 to 20 mg/l

• 0 to 400 hPa

• 0 to 200 % SAT

A0012885

Direction of medium flow

Cleanfit COA451

Sensor cable

4 Endress+Hauser

Oxymax COS61D/COS61

PK GY

COM A COM B

–

Power supply

Electrical connection

COS61D

Connection data

• Sensor cable connected directly to the terminal connector of the basic module

• Optional: sensor cable plug connected to the M12 sensor socket of the transmitter With this type of connection, the transmitter is already wired at the factory.

 3 Sensor fixed cable with terminated cable cores

COS61 to field device

You connect the sensor directly to the transmitter via the special measuring cable with SXP connector.

 4 SXP connector

Response time

COS61 to cabinet device

Terminal COM223

87 YE +U

0 GN 0 V WH 0 V

96 PK Communication (digital) GN Communication (digital)

97 BU Communication (digital) BN Communication (digital)

88 BN -U

Sensor with fixed cable (OMK) Sensor with TOP68 plug connection (CYK71)

Core Assignment Core Assignment

YE +U

Coax, inside -U

1. Remove the SXP connector (transmitter side!) from the cable.

2. Refer to the table for the cable assignment and terminals of Liquisys COM223-WX/WS.  Please note that the cable assignment varies depending on the sensor version (fixed cable

or TOP68 plug connection).

Performance characteristics

From air to nitrogen at reference operating conditions: t90 : 60 s

Endress+Hauser 5

+ 11 hidden pages