Oxygen analyzer SGM5

monitoringprocessfor the food industry

General information
The compact precision oxygen analyzer SGM5T integrates the calibration- and drift-free ZIROX zirconia measuring cell and an electronic unit for cell heating control, flow monitoring, signal processing and calculation of derived parameters. A microprocessor converts the cell signal to oxygen concentration using the Nernst equation. Measured values are available as an analog current (4–20 mA) and optionally via RS232; PC software for logging and visualization is available. The electronics can process an additional integrable sensor (e.g. CO2, humidity or pressure) with standard interface.

Special version SGM5S
The SGM5S variant is configured for measurements in CO2 atmospheres (brewery applications) and includes additional gas filtering and pressure-reduction components.

Applications
The SGM5 series is designed for process monitoring where oxygen traces affect product properties or processes under protective/inert gases. Typical uses include soldering and welding, heat treatment of metallic surfaces, microelectronics manufacturing, food packaging and brewery CO2 monitoring. Calculated indicators (redox quotient, air factor lambda, H2O/H2 or CO2/CO ratios) support control and documentation within quality management systems (e.g. ISO 9000).

Technical data Oxygen Analyzer SGM5T
Range: 2.0 · 10^5 ... 0.1 Vol.-ppm (20.6 ... 10^-4 Vol-%); measurements to 10^-20 Vol.-ppm on request; range to 100 Vol.-% on request
Signal output: 4–20 mA (options: 0–5 V, 0–10 V)
Accuracy at normal pressure: rel. error < 3% for 2 · 10^5 ... 10 ppm; rel. error < 5% for 10 ... 0.1 ppm
Gas flow: 5–10 l/h
Max. measuring gas pressure: 100 mbar overpressure (higher pressures require pressure reduction); >1 kPa overpressure requires error correction
Max. measuring gas temperature: 80 °C at gas inlet
Pressure drop over measuring cell: approx. 1 kPa at 10 l/h
Dimensions (D×W×H): 320 × 240 × 90 mm
Weight: 4 kg
Protection degree: IP30
Operating conditions: 10–40 °C, rel. humidity < 80% at 20 °C
Storage conditions: -20–60 °C, rel. humidity < 95% at 20 °C

Power supply
Voltage: 110–230 V / 50–60 Hz
Power consumption: 30 VA
Heating measuring cell: 24 V DC, approx. 15 W (internally controlled)

Keypad and display
Keypad: membrane keypad with 6 keys
Display: LCD dot-matrix (plain text)
Digital interface: RS232

Characteristics / specifications

• Measuring cell: calibration- and drift-free ZIROX zirconia measuring cell
• Measurement principle: microprocessor conversion using the Nernst equation
• Output signals: 4–20 mA (optional 0–5 V, 0–10 V) and RS232
• Optional calculations: air factor, redox quotient, H2O/H2-ratio, CO2/CO-ratio
• Optional integration of additional sensors (CO2, humidity, pressure)
• Wide measurement range down to 0.1 Vol.-ppm; extended ranges on request
• Gas flow 5–10 l/h; pressure drop approx. 1 kPa at 10 l/h
• Max. gas overpressure 100 mbar (pressure reduction required above)
• Operating temp 10–40 °C; storage -20–60 °C
• Dimensions 320×240×90 mm; weight 4 kg; protection IP30
• Power supply 110–230 V / 50–60 Hz; heating cell 24 V DC, ~15 W