Baker Hughes Druck DPS 8000 Series, Instruction Manual

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Copyright 2011 Baker Hughes Company.
8 | DPS 8000 Instruction Manual–English
• A CANopen software package to get access to the contents of the CANopen Object
Dictionary. Refer to Appendix A, “CANopen Object Dictionary,” on page 19.
3.6.4.2 Two-Point Pressure Calibration – Procedure
To get accurate results, calibrate in conditions where the pressure and temperature are stable.
1. Record the current values for the calibration data:
• Object 0x2207 00 (Pressure Gain) = GAIN
Default value = 1
• Object 0x2208 00 (Pressure Offset) = OFFSET
Default value = 0 mbar
2. First calibration point:
a. Apply Pressure (AP1) at 10% of the full-scale pressure (in mbar) and allow the pressure
to become stable.
b. Record the Field Value (FV1) that appears in object 0x6100 01 (Pressure Value).
Record the value in mbar.
3. Second calibration point:
a. Apply Pressure (AP2) at 90% of the full-scale pressure (in mbar) and allow the pressure
to become stable.
b. Record the Field Value (FV2) that appears in object 0x6100 01 (Pressure Value).
Record the value in mbar.
4. Calculate the new values for the calibration data:
• NEW GAIN = [GAIN] * [(AP1 - AP2) / (FV1 - FV2)]
• NEW OFFSET = [(OFFSET) - FV1] + [(AP1) * [(AP1 - AP2) / (FV1 - FV2)]]
The value for the NEW OFFSET is in mbar.
5. Write the new values for the calibration data back to the CANopen Object Dictionary:
a. Set object 0x2200 00 (calibration access pin) to 4118.
b. Set object 0x2207 00 (pressure gain) to the NEW GAIN value.
c. Set object 0x2208 00 (pressure offset) to the NEW OFFSET value. The value for the
NEW OFFSET is in mbar.
d. Set object 0x2200 00 (calibration access pin) to 0.
6. Confirm that the new values for the calibration data are correct:
a. Repeat steps 2 and 3.
7. Write the new values for the last and next calibration dates back to the CANopen Object
Dictionary:
a. Set object 0x2200
00 (Calibration Access Pin) to 4118.
b. Set objects 0x2201 00 to 0x2203 00 to the new values for the last calibration year,
month, day.
c. Set objects 0x2204 00 to 0x2206 00 to the new values for the next calibration year,
month, day.
d. Set object 0x2200 00 (Calibration Access Pin) to 0.
8. If applicable, reset the values for the out-of-limit counters (objects 0x2006 to 0x2009).
3.6.4.3 Two-Point Pressure Calibration – Results
For correct operation, the value for the NEW GAIN is in the range 0.9 to 1.1. If the value is not in
this range, this shows either a defective unit or defective calibration equipment.