Capacitance diaphragm gauge

Sensor body Signal converter (ceramic) j + amplifier 

1) Sensors Di 200 and Di 2000 with aiuminum oxide diaphragms, which are particuiariy overioad-free, with the MEMBRANOVAC DM 11 and DM 12 units. 

2) Sensors with inconei diaphragms CM 1, DM 10, CM 100, CM 1000 with extremeiy high resoiution, with the DM 21 and DM 22 units. 

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Another reference gauge is the VISCOVAC decrement gauge with rotating ball (see 3.3.1) as well as the capacitance diaphragm gauge (see 3.2.2.4). 

Capacitance diaphragm gauge FS= 1330 mbar Uncertainty = 0.2% reading... 

Figure 7.4 (a) Capacitive diaphragm gauge with metal diaphragm, (b) Capacitive... 

Pressure exerted on a surface with respect to a reference - e.g. support of a colunm of liquid as in a mercury manometer deflection of a diaphragm as in a capacitance diaphragm gauge (CDG). 

Figure 4.1 (a) The Capacitance Diaphragm Gauge (CDG) and (b) the Molecular Drag Gauge... 

As a general feature of most osmometers, the membrane is clamped into a stainless steel thermostated chamber (the measuring cell and the pressure measuring system of modem osmometers are built into a high-grade electronically stabilized thermostat) and serves as barrier between the pure solvent and the polymer solution sides of the chamber. The solvent side (bottom) is in juxtaposition with a pressure sensor, e.g., the diaphragm of a capacitance strain gauge or a piezo-chip. The solvent transport is measured across the... 

Vacuum gauge, capacitance manometer gauge A vacuum gauge that uses the deflection of a diaphragm, as measured by the changing capacitance (distance) between surfaces, as an indicator of the pressure differential across the diaphragm, the pressure on one side being a known value. 

On hard-to-handle services, such as the fluidized-bed level measurement in combustion processes, there is little choice but to use radiation gauges. On slurry and sludge services, d/p units with extended diaphragms eliminate the dead-ended cavity and bring the sensing diaphragm flush with the inner surface of the tank. Other level transmitters that can be considered for hard-to-handle services include the capacitance/RF, laser, radar, sonic, and TDR types. 

A capacitance manometer refers to the device that senses the deflection of the diaphragm. Capacitance manometers are typically an order of magnitude more accurate than standard capsule dial gauges. 

The effect on the height of a column of liquid, deformations in flexible membranes amplified and made visible, resistance change strain gauge, resonant phenomena, piezoresistivity, diaphragm and plate capacitance, electrets... 

In most cases the pressure is detected using diaphragm sensors classified in terms of sensing element as metal strain gauge, piezoelectric semiconductor, electric capacitance, reluctance, and LVDT (linear variable-differential transformers) sensors. The structure of a silicon semiconductor sensor, where the pressure is detected by a silicon diaphragm, is shown in Fig. 5. In most cases these sensors can be used at temperatures lower than 70°C. 

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