Operation Of The Instrument - Chauvin Arnoux CA850 Notice D'utilisation

4. OPERATION OF THE INSTRUMENT

4.1 " Monitoring " mode
When you press the «REC» button, you access the «monitoring» mode.
Before going into this mode, select the unit of pressure, as you will not be able to change it
once you are in monitoring mode.
When you press the button, a clock is started and "REC" is displayed on the screen.
This mode enables you to time/date-stamp the maximum and minimum values in your
measuring operation.
When you press the "REC" button a second time, MAX is displayed on the screen and the
maximum value from the measuring operation is indicated on the main screen. The clock
indicates the time when this event occurred during the measuring operation.
When you press a third time, you obtain the same information for the minimum value.
A fourth press returns you to the current value.
To exit from this mode, press the "REC" button for 3 seconds.
Note: The "differential measurement" mode is not accessible from the "monitoring" mode.
4.2 " Differential measurement " mode
When you press the «DIF» button, you access the «differential measurement» mode.
The differential measurement mode measures the difference between two pressures. But it
can also be used to quantify pressure variations (connect one input to your system and
leave the other at atmospheric pressure).
Before going into this mode, select the unit of pressure, as you will not be able to change it
once you are in monitoring mode.
When you press the button, the "DIF" symbol and the relative zero are displayed on the
screen. From now on, only the pressure change will be indicated.
To exit from this mode, press the "DIF" button.
4.3 Adjustment of the zero
Leave the inputs at atmospheric pressure and press the «HOLD» button for 2 seconds. The
screen switches off, indicates «0.0.0.0» from right to left and then the zero is displayed.
4.4 Calibration and adjustment of the instrument
Calibration can only be performed using a pressure calibrator.
First, set the zero
Then switch off the instrument
Press the "REC" and "power" buttons simultaneously. "CA" appears on the screen. You
are now in setting mode.
Check that the unit selected is "psi" before starting to adjust the positive input.
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