Emerson 51-DO-03, 51-DO-04 instruction manual Section Specifications, Features and Benefits

Page 7

MODEL DO-03/04

SECTION 1.0

 

SPECIFICATIONS

SECTION 1.0

SPECIFICATIONS

COMPLETE SYSTEM INCLUDES sensor, analyzer, sensor washer head, mounting hard- ware, and air compressor.

• AIR BLAST CLEANER system can keep DO sensors funtioning up to 3 months or longer.

SENSOR MAINTENANCE is quick and easy.

FEATURE-PACKED ANALYZER: on-board pressure sensor for completely automatic air calibration, large backlit display, dual outputs, three fully programmable alarm relays.

FEATURES AND BENEFITS

The Model DO-03/04 is a complete system for the determination of dissolved oxygen in wastewater aeration basins. It consists of a sensor, an analyzer, a handrail mounting assembly, a sensor washer head, and an air compressor. A timer in the analyzer allows the user to customize the air blast cleaning cycle.

The Model DO-03/04 uses a membrane-covered amperometric sensor. A polarizing voltage applied to a gold cathode behind the membrane destroys oxygen diffusing through the membrane and keeps the concentration of oxygen in the sensor equal to zero. The current generated by the cathode reaction is proportional to the rate of diffusion of oxygen through the membrane. Because the concentration of oxygen in the sensor is zero, the diffu- sion rate and the current are proportional to the concentration of oxygen in the sample.

Sensor maintenance is fast and easy. Replacing a membrane requires no special tools or fixtures. A screw cap holds the pre-tensioned membrane in place. Replacing the electrolyte solution takes only minutes.

The Model DO-03/04 includes the rugged, easy-to-use Model 54eA analyzer. The analyzer features two fully pro- grammable 4-20 mA outputs, and three fully programmable alarm relays. The backlit three line display allows the user to read oxygen levels at a glance. The analyzer permits both air calibration and calibration against a labora- tory instrument. Air calibration is completely automatic. All the user does is expose the sensor to water-saturated air and press a few buttons.

The Air Blast Sensor Cleaner, which includes the washer head and air compressor, keeps the sensor membrane clean, helping ensure reliable, trouble-free oxygen measurements and reducing sensor cleaning maintenance to as little as every three months. At programmed intervals, the air blast cleaner blows a stream of air across the membrane to clear bio-film from on the membrane. The frequency and duration of the air blast is programmable from the 54eA analyzer.

The photograph shows a sensor after nine weeks in an aeration basin. The cathode is clearly visible under the membrane. A 60-second air blast every eight hours is keeping the membrane clean.

Plant service air can be used in place of the air compressor. The 54eA analyzer relay is then used to operate a solenoid valve.

1

Image 7
Contents Model DO-03/04 Dissolved Oxygen Measurement System with Air Blast CleanerEssential Instructions Page Section Title Model DO-03/04 Measuring System10.0 List of Tables11.0 Section Title List of FiguresIii Features and Benefits Section SpecificationsOutput Accuracy ± 0.05 mA PowerRepeatability ±0.05 ppm 25C RFI/EMI EN-61326Maximum distance between compressor and sensor Maximum continuous pressure 50 psig 446 kPa absMaterials of Construction Analyzer dimensions Enclosure dimensions Description Power required selection9240048-00 Tag, stainless steel, specify marking Model or part number Description Section InstallationInstallation Unpacking and InspectionInstalling the handrail mounting assembly Installing the air compressor enclosureAssembling the pipe and pipe clamp Attaching the pipe boom to the handrail mounting assembly Installing the sensor in the washer head assemblyAssembling the washer head and pipe boom Attaching the air compressor enclosure to the handrail Installing the sensor in the washer head assembly POWER, ALARM, and Output Wiring Section WiringGeneral 454EPH02 Section Section Wiring the Oxygen Sensor Sensor WiringGeneral KEY Functions and Control Alarm StatusSection Display and Operation DisplayMenu Tree for the 54eA Analyzer Section Software ConfigurationOn following Main Menu Calibrate See Diagnostic Variable see Choices Factory Settings Setpoints Program Settings ListChoices Factory Settings Configure Choices Factory Settings Alarm 3 setpoint Alarm setpointsAlarm 1 setpoint Alarm 2 setpointRanging the Outputs MA 0.00 ppm 20 mA 20.00 ppm Output 1 12.00 mASimulated tests Test alarm 1 OpenTest output Meas units ppm Outputs AlarmsDisplay Measure OxygenTemp units C Output 1 mA Output 2 mA Display contrast Timeout OnLanguage English Display left Display right Out Output 1 control OutputsOutput Measurement Output 1 Control Output 1 SetupRange 4-20 mA Dampen 0 sec Hold Last Value Changing Alarm Parameters ConfigureAlarm 1 control Alarm 1 setup Alarm 2 controlActivate Process Alarm 1 controlAlarm 1 setup Alarm LowAlarm 4 setup Alarm FaultFeed limit Disable Timeout 3600 secInterval timer setup Alarm 4 setup Feed limit timerInterval timer Timer Disable Timer Time activated Interval 24.0 hrTemp comp Manual Temp units C Temperature Compensation and Temperature UnitsTemp comp Auto Temp units CNoise Reduction 60 HzBar units mm Hg Bar meas AutoBarometric Pressure Salinity 0.0 o/oo Main sensor calSecurity Noise rejection Main sensor cal SecurityCondition Definitions Analyzer Mode PriorityAction Definitions Introduction Section Calibration TemperatureTemperature Calibration Adjust temp + 025.1 CSensor Current as a Function Dissolved Oxygen Concentration Section Calibration Dissolved OxygenZeroing the Sensor Sensor must be in zero solutionCalibrating the Sensor in AIR Stabilizing . . . WaitSection Calibrating the Sensor Against a Standard Instrument Calibrate 8.32 ppmCalibrating Barometric Pressure Zero main sensor Adjust temperatureCalibrate main sensor StandardizeTrimming the Outputs Section Calibration Current OutputsReplacing electrolyte solution and membrane Section MaintenanceReplacement Parts Cleaning the membraneSection Spare Parts Power FuseAIR Blast Sensor Washer Replacement Parts Location Part Number DescriptionOverview Section TroubleshootingTroubleshooting When a Fault Message is Showing Fault message Explanation See SectionSense line open Temperature error low or highHigh input current Check sensor zeroProblem See Section Troubleshooting When no Fault Message is Showing OxygenZero current is too high Zero reading Is unstable Possible error warning during in-process calibrationBarometric pressure reading is too high or too low Oxygen readings are too low Process readings are erraticReadings drift Sensor does not respond to changes in oxygen levelSensor Polarizing Voltage Resistance Expected current Troubleshooting not Related to Measurement ProblemsProblem Action Simulating Inputs Dissolved OxygenSimulating temperature Simulating TemperatureGeneral Section Return of MaterialSensor or Circuit Board only Return of Materials RequestWarranty Specifications subject to change without notice