PXU Input Calibration

Please Note

Entering calibration may void the factory warranty.

 The controller has been fully calibrated at the factory. Scaling to convert the input signal to a desired display value is performed in Configuration Module 1, Input Parameters. If the controller appears to be indicating incorrectly or inaccurately, refer to Troubleshooting before attempting to calibrate the controller. 

Recalibration should only be performed if necessary and only by qualified technicians using appropriate calibration equipment.

NOTE 1: Module 1 program parameter may be changed during calibration.  Entering CodE 48 will require that Input Parameters (Module 1) be verified after calibration is complete. 

NOTE 2: For all calibrations, allow the controller to warm up for 30 minutes minimum and follow the manufacturer’s warm-up recommendations for the calibration source or measuring device.

APPLICABLE PRODUCTS 

• All PXU series PID process controls 

PRE-REQUISITES 

• PXU series PID process control 
• Quality analog signal simulator 
• Allow PXU unit to be powered on for 30 minutes prior to calibration

IN THIS ARTICLE 

Calibrating the unit to correct when the controller appears to be indicating incorrectly or inaccurately, even after troubleshooting with the factory. 

• Thermocouple input calibration
• Voltage input calibration
• RTD input calibration
• CJC calibration

Thermocouple Input Calibration

1. Apply power and allow unit to stabilize for 30 minutes.
2. Apply 0uV to input terminals 11(+) and 12(-).
3. Access CNFP 9, Select CodE 48.
4. If top display value is zero, press P and go to Step 7.
5. If top display is positive value, using the Dn key decrease the bottom display value by the number shown on the top display. Press P and go back to Step 4.
6. If top display is negative value, using the Up key increase the bottom display value by the number by the absolute number shown on the top display. Press P and go back to Step 4.
7. Apply 9000uV to input terminals 11(+) and 12(-) and allow top line to stabilize.
8. If top display value is 9000, press P and go to Step 11.
9. If top display is greater than 9000, using the Dn key decrease the bottom display value by the number shown on the top display - 9000. Press P and go back to Step 8.
10. If top display is less than 9000, using the Up key increase the bottom display value by the 9000 – the number shown on the top display. Press P and go back to Step 8.
11. Press “D”.
12. TC Calibration is complete.
13. Reminder: Verify Module 1 program settings.

Voltage Input Calibration

1. Apply power and allow unit to stabilize for 30 minutes.
2. Apply 0 V to input terminals 11(+) and 12(-).
3. Access CNFP 9, Select CodE 48.
4. Press “P” 3 times, or until bottom line displays “MuF”
5. If top display value is zero, press P and go to Step 8.
6. If top display is positive value, using the Dn key decrease the bottom display value by the number shown on the top display. Press P and go back to Step 5.
7. If top display is negative value, using the Up key increase the bottom display value by the number by the absolute number shown on the top display. Press P and go back to Step 5.
8. Apply 5 V to input terminals 11(+) and 12(-).
9. If top display value is 5000, press P and go to Step 12.
10. If top display is greater than 5000, using the Dn key decrease the bottom display value by the number shown on the top display - 5000. Press P and go back to Step 9.
11. If top display is less than 5000, using the Up key increase the bottom display value by the 5000 – the number shown on the top display. Press P and go back to Step 9.
12. Press “D”.
13. Volt Input Calibration is complete.
14. Reminder: Verify Module 1 program settings.

RTD Input Calibration

1. Set Input Type to “r385” and set input scale to “°C”.
2. Apply 100.00 ohm resistance to terminal 10 and 11/12.
3. Access CNFP 9, select CodE 48.
4. Press “P” 5 times, or until bottom line displays “rt-F”
5. If top display value is 0.0, press P and go to Step 8.
6. If top display is positive value, using the Dn key decrease the bottom display value by the number shown on the top display. Press P and go back to Step 5.
7. If top display is negative value, using the Up key increase the bottom display value by the number by the absolute number shown on the top display. Press P and go back to Step 5.
8. Apply 280.93 Ohms resistance to input terminals 11(+) and 12(-).
9. If top display value is 500.0, press P and go to Step 12.
10. If top display is greater than 500.0, using the Dn key decrease the bottom display value by the number shown on the top display – 500.0. Press P and go back to Step 9.
11. If top display is less than 500.0, using the Up key increase the bottom display value by the 500.0 – the number shown on the top display. Press P and go back to Step 9.
12. Press “D”.
13. RTD Input Calibration is complete.
14. Reminder: Verify Module 1 program settings.

Cold Junction Compensation Calibration

1. Perform TC Calibration.
2. Connect precision thermocouple sensor.
3. Program “tyPE” to match the precision thermocouple type connected.
4. Program display to read in °C.
5. Access CNFP 9, select CodE 48.
6. Press “P” 7 times, or until bottom line displays “CJ-F”
7. If top display value is equal to the thermocouple tip temperatue, press P and go to Step 10.
8. If top display is greater than the thermocouple tip temperature, using the Dn key decrease the bottom display value by the number shown on the top display – the thermocouple tip temp. Press P and go back to Step 9.
9. If top display is less than the thermocouple tip temperature, using the Up key increase the bottom display value by the thermocouple tip temp – the number shown on the top display. Press P and go back to Step 9.
10. Press “D”.
11. Cold Junction Input Calibration is complete.
12. Reminder: Verify Module 1 program settings.

ADDITIONAL INFO 

Link to PXU product manual 

HMS Support 

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