Drawing Number: 21070
Revision: NR
OPERATION MANUAL FOR
ICP
®
PRESSURE SENSORS
Models 102A02, A05, A07, A09
Models 112A21, A22, A23
3
Defined for practical purposes as the minimum
readout signal, the resolution is based on the
sensitivity of 50 mV/psi and a low noise amplifier of
50
V peak noise.
Thus, 50
V/50mV = .001 psi resolution
The output bias voltage of the Model 112A23 is 5.0
volts, half the bias voltage of most PCB pressure
sensors. This will cause the bias monitor meter on
PCB power supplies to read at the low end of the
green band.
5.0
POLARITY
This sensor series produces a positive-going output
voltage for increasing pressure input.
6.0
LOW FREQUENCY RESPONSE
The low frequency response of an ICP
system is
determined by:
1.
The discharge time constant of the sensor,
and,
2.
If AC-coupled at power unit, the coupling
time constant.
Consult Section 7.0 in Guide G-0001B for detailed
explanation of low frequency characteristics of ICP
instruments.
7.0
CALIBRATION
Piezoelectric sensors are dynamic devices, but static
calibration methods may be employed if discharge
time constants are sufficiently long. Generally, static
methods are not employed below several hundred
seconds discharge time constant.
To employ static methods, directly couple the sensor
to the DVM readout using a T-connector from the
XDCR jack or use the Model 484B in the "calibrate"
mode. Apply pressure with dead weight tester and
take readings quickly. Release pressure after each
calibration point.
For the shorter discharge time constant series, a rapid
pressure step must be generated by a pneumatic
pressure pulse calibrator or dead weight tester and
readout is by recorder or storage oscilloscope.
PCB offers a complete recalibration service. Consult
factory for details.
Содержание SM102A07
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