Two-Point Pressure Calibration (Absolute Transducers) - Honeywell ERX User Manual

6. Select "Calibrate" from the main menu.
7. Select "Pressure Calibration" from the sub-menu.
8. With zero pressure applied to the ERX pressure transducer, perform the "Pressure Zero
Calibration." The pressure displayed in green on the computer's screen is a live reading.
This permits the user to determine if the pressure has stabilized so that a sample may be
obtained. Click the AVERAGE PRESSURE NOW button when it becomes active (text
changes from gray to black) to obtain a sample of the applied pressure.
9. When MasterLink32 displays "Average Pressure", the value should be changed to match
the pressure reference by clicking the CHANGE button when it becomes active. Enter
the pressure value for the zero reference pressure (usually 0.00). The ERX will calculate
the required difference offset, store this calculated value within the instrument before
returning to a live pressure reading.
10. Compare the displayed pressure to the reference pressure. If the ERX pressure reading is
not acceptable, click the AVERAGE PRESSURE NOW button again to obtain another
pressure sample. The program will continue to loop back to the live pressure reading.
Obtain as many pressure samples as necessary until an acceptable pressure reading is
displayed.
11. If the ERX zero pressure reading is acceptable, click the SPAN button to change to the
Span Calibration sequence.
12. The screen title should have changed to "Pressure Span Calibration." At this point, the
software is waiting to sample the applied pressure. Increase the pressure applied to the
ERX to the span reference pressure. This must be greater than 50% of the transducer
range.
Example #1: If the zero reference pressure on a 100 PSI transducer equals 0.00 PSI, then
the span reference pressure must be between 50.00 and 100.00 PSI.
Example #2: If the zero reference pressure on a 600 PSI transducer equals 0.00 PSI, then
the span reference pressure must be between 300.00 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 pressure has stabilized, click the
AVERAGE PRESSURE NOW button when it becomes active to obtain a pressure
sample.
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,
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 pressure reading to the span reference pressure. If the average
pressure reading is acceptable, 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.

Two-Point Pressure Calibration (Absolute Transducers)

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