CMR 273 Pressure Sensor - Good Condition 2005

CMR 273 pressure sensor: precision and reliability for vacuum environments

Pfeiffer Vacuum's CMR 273 sensor is designed for absolute pressure measurement in vacuum systems, with a measuring range from 10⁻³ to 11 mbar. This sensor uses a capacitive aluminium oxide ceramic diaphragm, combined with conversion electronics that transform the capacitive signal into a linear DC voltage output. This linearity ensures reliable and reproducible readings, regardless of the type of gas being measured, making it particularly suitable for multi-gas environments or complex processes.

Thanks to its compact design and low sensitivity to vibrations, the CMR 273 can be installed in various orientations without compromising measurement accuracy. It is compatible with Pfeiffer Vacuum measuring units for compact sensors, but can also be integrated into other evaluation systems via customised cabling. Its fast response time of 30 ms enables dynamic monitoring of pressure variations, which is essential in real-time control processes.

High-precision vacuum instrumentation for laboratories and industry

The CMR 273 is particularly suitable for applications requiring high accuracy at low pressures, such as vacuum deposition processes, spectrometric analyses or scientific research environments. Its remarkable thermal stability, with a zero drift of less than 0.0025% F.S./°C, allows reliable use even under fluctuating temperature conditions. In addition, its construction from corrosion-resistant materials, such as AISI 316L stainless steel and Al₂O₃ ceramic, ensures exceptional durability in the presence of aggressive gases or contaminants.

The sensor is protected against polarity reversal and short circuits, and its output signal is secured for minimum loads of 10 kΩ. It can be used up to a maximum pressure of 1.3 bar absolute, and its reduced internal volume limits the effects of contamination. To optimise performance, it is recommended that the sensor be kept evacuated during system venting phases.

Compact solution for pressure monitoring in vacuum systems

The CMR 273 offers a resolution of 0.0015% F.S., enabling fine detection of pressure variations, even in the lowest ranges. Its compact design facilitates integration into existing installations, and its compatibility with different types of flanges (1/2", ISO-KF, CF-R, VCR) offers considerable installation flexibility. If necessary, the sensor can be readjusted or cleaned according to specified procedures without interfering with the measuring chamber.

• Measuring range: 10⁻³ to 11 mbar (10 mbar F.S.)
• Resolution: 0.0015% F.S.
• Accuracy: 0.15% of measured value
• Temperature effect on zero: 0.0025% F.S./°C
• Temperature effect on span: 0.01% of measured value/°C
• Output signal: 1.0 V to 9.8 V linear
• Response time: 30 ms
• Output impedance: < 10 Ω
• Minimum load: 10 kΩ, short-circuit protection
• Internal volume: 7.25 cm³ (1/2"), 9.25 cm³ (ISO-KF, CF-R, VCR)
• Operating temperature: +15 °C to +40 °C
• Storage temperature: -40 °C to +65 °C
• Degassing temperature: +90 °C max. at the flange
• Relative humidity: max. 80% at ≤ +31 °C
• Materials in contact with the vacuum: AISI 316L stainless steel, Al₂O₃ ceramic > 99.5%
• Protection type: IP 30