Pressure, Dc Current, And Dc Voltage Source And Measurement Functions - YOKOGAWA CA700-01 User Manual

1.2 Pressure, DC Current, and DC Voltage Source
and Measurement Functions
Pressure Measurement
Liquid and gas pressure can be measured.
Gauge Pressure Measurement and Absolute Pressure
Measurement
There are two methods to measuring pressure: gauge pressure measurement, which takes
atmospheric pressure to be zero, and absolute pressure measurement, which takes vacuum to be
zero.
The CA700 comes in three types depending on the gauge pressure that can be measured.
CA700-01 –80 kPa to 200 kPa
CA700-02 –80 kPa to 1000 kPa
CA700-03 –80 kPa to 3500 kPa
Leak Rate Measurement
You can apply pressure to the device under measurement and measure the pressure over a given
period to examine the pressure change caused by leakage.
The display shows the pressure at the start of measurement, the pressure at the end of measurement,
the amount of pressure change, and the amount of pressure change per unit time (leak rate).
Zero Calibration
When the pressure sensor inside the CA700 is used to make measurements, measured values may
be affected by the measuring environment and orientation of the CA700. Zero calibration (ZERO CAL)
refers to the act of compensating for these effects.
A sensor inside the CA700 detects how much the CA700 is tilted. If the orientation is changed after a
zero calibration is performed, the "ZERO CAL" indicator blinks to alert the user.
Combination with DC Current and DC Voltage Source and
Measurement
DC current and DC voltage can be generated and measured simultaneously while pressure is being
measured. However, during leak rate measurement, only leak rate measurement and generation are
possible.
The possible combinations are (1) pressure measurement and DC current generation, (2) pressure
measurement and DC voltage generation, (3) pressure measurement and DC current measurement,
and (4) pressure measurement and DC voltage measurement. The transmitter input pressure and
transmitter output can be measured simultaneously.
Averaging
The CA700 can take a moving average of the measured values and display the results. If averaging is
on, relative display (RELATIVE) and max/min display (MIN/MAX) use averaged values.
Scaling
By assigning scale values to the upper and lower limits of the span, you can linearly scale measured
values and display the scaled results. If scaling is enabled, you can assign an appropriate unit.
Alarm
When a measured value exceeds the specified range, the value will blink, and an alarm mark will
appear. If the relative display feature (RELATIVE) is enabled, the CA700 uses the measured values,
not the relative values, to make this decision. This feature is not available for leak rate measurement.
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IM CA700-01EN