OMA-406-O2 Analyzer

Applications

The OMA-406-O2 can be used to monitor sulfur dioxide and oxygen in the following processes:

• Continuous emissions monitoring.

Technology

Paramagnetic Oxygen Detection

• Unlike most gases oxygen is paramagnetic. This means that it is weakly attracted to a magnetic field when placed in the presence of a magnetic field. A paramagnetic sensor uses this fact to determine oxygen concentration.
• The sample enters the enclosure containing a torsion balance suspended in a magnetic field.
• An oxygen containing sample will cause the cause the balance to deflect from its zero position.
• A photodetector measures the deflection and provides a feedback current to restore the torsion balance to its zero position.
• The feedback current is directly proportional to oxygen levels in the sample after calibration.

Spectroscopy

To analyze the chemical composition of the sample, the OMA uses an analysis method known as ultraviolet-visible (UV-Vis) spectroscopy. The system measures absorbance from 200nm to 800nm and quantifies the amount of light absorbed by the sample at each integer wavelength; the OMA plots this raw data to visualize a high-resolution absorbance spectrum. Learn more

The OMA uses a long-life xenon light source to transmit a signal through the sample fluid in the flow cell. The signal is carried by fiber optic cables from the analyzer to the flow cell, where the chemical mixture of the sample has unique interactions with the light based on its current composition. Learn more

Specifications

General
Detector	nova II™ spectrophotometer, paramagnetic oxygen detector
Spectrometer Light Source	Standard: pulsed xenon lamp with average 5 year life span
Fiber Optic Cables	Standard: 600 μm core 1.8-meter fiber optic cables (qty = 2)
Process Connection	1/4” tubing compression fitting (flow cell) and 1/8” tubing compression fitting (oxygen detector)
Calibration	If possible, the instrument is factory calibrated prior to shipment; Monthly calibrations are required to keep O2 sensor within specification. Spectrophotometer does not require calibration after the initial calibration.
Human Machine Interface	Industrial controller with touchscreen LCD display running ECLIPSETM software
Data Storage	Solid state drive
Measuring Parameters
Accuracy	Spectrometer: ±2% full scale range
Response Time	Readings every 1-5 seconds
Sample Parameters
Sample Temperature	Standard: 0 to 65 °C Contact AAI for temperatures above these ranges
Sample Pressure	Standard: -5 psig to 5 psig
Sample Medium	Gas
Flow Rate	50-200ml/min
Ambient Conditions
Analyzer Environment	Indoor
Ambient Temperature	Standard: 0 to 35 °C (32 to 95 °F)
Ambient Altitude	-250 m to 5,000 m (-770 ft to 15,400 ft)
Physical Specifications
Dimensions	8.90" H x 19.02" W x 14.29" D (226mm H x 483mm W x 363mm D)
Analyzer Weight	30 lbs. (14 kg)
Wetted Materials	Flow cell: fused silica, viton, 316L stainless steel Oxygen sensor: 316 stainless steel, viton, borosilicate glass, electroless nickel, platinum/iridium alloy
Electrical Requirements	85 to 264 VAC 47 to 63 Hz
Power Consumption	45 Watts
Outputs	1x galvanically isolated 4-20mA analog output per measured analyte 2x digital outputs for fault and SCS control Optional: Modbus TCP/IP; RS-232; RS-485; HART; Contact AAI for options not listed

Resources