Calibration Calibration can be done on two levels 1. I/O calibration Calibration of analog inputs, PT-100 inputs and analog outputs 2. Calibration of process inputs Loop calibration of any process input (temperature, pressure, density, viscosity, BS&W, differential pressure) that is read through an analog, PT-100, HART, Modbus or densitometer input. Display → Maintenance, Calibration If calibration / verification remains active and / or the inputs remain frozen without any command being given for more than the Calibration inactivity timeout, calibration will be aborted and the inputs will be unfrozen. I/O calibration / verification Although all module I/O has been calibrated before leaving the factory, an additional calibration can be done. Furthermore, a verification procedure can be followed and a verification report can be printed. Follow this procedure to calibrate or verify the inputs and outputs of a module. 1. Select ‘Module IO’ (1, 2, … refers to module number) This brings up an overview of the analog inputs, PT100 inputs and analog outputs that have been configured on this module 2. Select the input or output to be calibrated / verified 3. Click ‘Freeze inputs’ (optional) Whether this is needed or not depends on the configuration parameter Freeze inputs is required (display Configuration, System settings, Calibration settings). The freeze command freezes all analog and PT100 inputs on the selected module, such that metering can go on using the frozen values, while calibration can be done using the live values. Not applicable to analog outputs. 4. Click ‘Clear calibration data’ (optional) This clears any existing calibration data from the previous calibration. When doing a recalibration, the command may be used to wipe out previous data, but it’s not needed, as the old calibration data will be replaced by the results of the new calibration anyway. 5. Click ‘Start calibration’ or ‘Start verification’. ‘Calibration’ means that the calibration results will be stored on the flow computer, allowing the flow computer to correct the input value. ‘Verification’ means that only a report will be generated, without storing the calibration data for correction. 6. Enter the reference value (mA) or (V) for analog inputs, depending on the analog input type; (°F) for PT100 inputs; (mA) for analog outputs. 7. The flow computer shows the actual uncorrected value and the deviation from the reference value 8. Click ‘Apply value’. Accepts the current point. Values of the current point can be overwritten until the 'Go to next Point' or 'Finish' button is selected. 9. Click ‘Go to next point’ This will activate the next calibration point. Max. 5 points can be used for calibration or 8 for verification. Repeat steps 6. to 9. for each consecutive calibration point. 10. Click ‘Finish’ This command is available when at least 2 points have been calibrated / verified. It logs the results and, in case of a calibration, stores the calibration data. 11. Click ‘Deselect’ to go back to the overview of configured I/O. From here you can start calibration / verification of the other inputs / outputs on the module. 12. If you’re done with calibration / verification of the I/O of this module, click ‘Deselect’ to return to the main calibration screen. For analog outputs also a zero offset can be specified. In order to apply an offset, follow steps 1-2 of above procedure to select the correct analog output and proceed as follows: 3. Enter the zero offset value (mA) 4. Click ‘Set zero offset’ Process input calibration / verification For each process input that receives its value through an analog, PT-100, HART, Modbus or densitometer input both a calibration curve and an offset is available. Calibration curves and offsets can be used simultaneously. Follow this procedure to calibrate or verify the flow computer’s process inputs. 1. Select any of the following buttons - Run process inputs (1, 2, … refers to run number) - Station process inputs - Prover process inputs - Auxiliary inputs This brings up an overview of the process inputs that have been configured on the flow computer 2. Click ‘Freeze inputs’ (optional)  Whether this is needed or not depends on the configuration parameter Freeze inputs is required (display Configuration, System settings, Calibration settings). The freeze command freezes all process inputs of the selected run / all station inputs / all auxiliary inputs / all proving inputs, such that metering can go on using the frozen values, while calibration can be done using the live values. 3. Select the process input to be calibrated / verified 4. Click ‘Clear calibration data’ (optional) This clears any existing calibration data from the previous calibration. When doing a recalibration, the command may be used to wipe out previous data, but it’s not needed, as the old calibration data will be replaced by the results of the new calibration anyway. 5. Click ‘Start calibration’ or ‘Start verification’. ‘Calibration’ means that the calibration results will be stored on the flow computer, allowing the flow computer to correct the input value. ‘Verification’ means that only a report will be generated, without storing the calibration data for correction. 6. Enter the reference value The unit is the standard unit for the selected process input: - temperature (°F) - pressure (psi) - BS&W (%) - Viscosity (cSt) - Density (-), (°API) or g/cc, depending on the input’s configured density input type - Differential pressure (inH2O@60F) 7. The flow computer shows the actual uncorrected value and the deviation from the reference value 8. Click ‘Apply value’. Accepts the current point. Values of the current point can be overwritten until the 'Go to next Point' or 'Finish' button is selected. 9. Click ‘Go to next point’ This will activate the next calibration point. Max. 5 points can be used for calibration or 8 for verification. Repeat steps 6. to 9. for each consecutive calibration point. 10. Click ‘Finish’ This command is available when at least 2 points have been calibrated / verified. It logs the results and, in case of a calibration, stores the calibration data. 11. Click ‘Deselect’ to go back to the overview of process inputs. From here you can start calibration / verification of the other process inputs. 12. If you’re done with calibration / verification of the process inputs, click ‘Release inputs’ (if needed, see above). 13. Click ‘Deselect’ to return to the main calibration screen. In order to apply an offset, follow steps 1-3 of above procedure to select the correct process input and proceed as follows: 4. Enter the zero offset value The unit is the standard unit for the selected process input: - temperature (°F) - pressure (psi) - BS&W (%) - Viscosity (cSt) (kinematic) - Density (-), (°API) or (g/cc), depending on the input’s configured density input type - Differential pressure (inH2O@60F) 5. Click ‘Set zero offset’