Honeywell ERX User Manual page 21

Example #1: If the zero reference pressure on a 100 PSIA transducer equals 14.73 PSIA,
then the span reference pressure must be between 64.73 and 100.00 PSI.
Example #2: If the zero reference pressure on a 100 PSIA transducer equals 13.25 PSIA,
then the span reference pressure must be between 63.25 and 100.00 PSI.
Example #3: If the zero reference pressure on a 600 PSIA transducer equals 14.73 PSIA,
then the span reference pressure must be between 314.73 and 600.00 PSI.
13. The span calibration also displays a live pressure reading to allow the user to determine if
the span reference pressure has stabilized. When the absolute pressure has stabilized,
click the AVERAGE PRESSURE NOW button when it becomes active to obtain a
pressure sample.
NOTE: The span reference pressure is equal to the sum of the dead weight tester
pressure, and the atmospheric pressure obtained in step 9 above.
14. If the average pressure reading is not equal to the span reference pressure, click the
CHANGE button when it becomes active. Enter the pressure value for the span reference
pressure. As the computer screen updates, the ERX will calculate the required span gain,
and store this calculated value within the instrument before returning to a live pressure
reading. Obtain as many pressure samples as necessary until an acceptable span pressure
reading is displayed.
15. Compare the average, absolute pressure reading to the span reference pressure. If the
average pressure reading is equal to the sum of the applied pressure plus the atmospheric
pressure, the pressure calibration process is complete. As a suggestion, recheck the
pressure zero reading and any number of pressure points within the transducer range, or
click DONE to exit the calibration sequence.
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