Two options are specific to calibrating Smart Valve hardware. These options can be found in Communications-> Smart Valve.
- Calibrate Torque
- Calibrate Pressure
Calibrate Torque
Calibration cannot take place unless a connection is present between the Schema Viewer PC and the valve. This can be accomplished with an I/R wand or, in this case, an Ethernet connection as indicated by the green box at the bottom of the dialog.
Torque Sensor Voltage, is the voltage measured from the torque sensor (in milliVolts) corresponding to the current load applied to the sensor.
Calibrated Torque displays the load applied to the torque sensor as a percentage of the actuators maximum torque value. Negative values correspond to closing torques. Positive values correspond to opening torques.
Calibration Values are set by applying a known torque to the actuator output (-100%, -30%, +30% and +100%). Pressing the Set button to record the voltage (in milliVolts) corresponding to each applied torque. Once the values are set, they must be downloaded to the actuator by pressing Save to Hardware.
Save to Hardware. Pressing this button will download the Calibration Values to the actuator. This action will overwrite any existing values stored in hardware.
Load from Hardware will upload the current calibration values stored in the actuator and display them in Calibration Values. Once loaded the Calibrated Torque value will display the correct percentage torque. The uploaded values can then be saved to file for later use.
Save to File. Pressing this button will save the values displayed in Calibration Values to a file. The user will be prompted for a file name prior to saving.
Load from File. Calibration values stored via the Save to File option can be retrieved by pressing this button. The user will be prompted to select a file from a File Open dialog. The loaded data will be displayed in Calibration Values and can be then downloaded to the hardware.
Calibrate Pressure
The calibration values are shown in two tabs, Gauge Pressure and Differential Pressure.
Calibration cannot take place unless a connection is present between the Schema Viewer PC and the valve. This can be accomplished with an I/R wand or, in this case, an Ethernet connection as indicated by the green box at the bottom of the dialog
The current values are displayed at the top of the dialog. Fluid pressure at sensor A and B are displayed in milliVolts along with the calibrated pressure in pounds per square inch and the percentage of the sensor maximum pressure. The Smart Valve hardware has circuitry to generate a separate differential pressure reading; the value displayed is the output from this circuitry and may not be the arithmetic difference of the Pressure Sensor A and Pressure Sensor B reading.
Gauge Pressure Tab Calibration Values are set by applying a pressure to both pressure sensors simultaneously at, 0%, 50%, and 100%. The values of the pressure to be applied are shown to the right of the percent values, e.g. in the Gauge Pressure figure, 50% corresponds to an applied pressure 250psi. Calibration is performed by stepping through each applied pressure and pressing the Set button to record each calibration voltage value (in milliVolts). Once the values are set, they must be downloaded to the actuator by pressing Save to Hardware. The pressures to be applied at each step will automatically change based on the pressure sensors fitted to the actuator.
Differential Pressure Tab Calibration Values are set by applying the same pressure to both pressure sensors in all steps except one. The two values of pressure to be applied are shown at each step, e.g. in Differential Pressure figure, the same pressure can be seen in each step except for step one where 0 psi is to be applied to Sensor A and 15psi is to be applied to Sensor B. Calibration is performed by stepping through each applied pressure step and pressing the Set button to record each calibration voltage value (in milliVolts). Once the values are set, they must be downloaded to the actuator by pressing Save to Hardware. The applied pressures, and the number of calibration steps, will automatically change based on the pressure sensors fitted to the actuator.
Save to Hardware. Pressing this button will download the Calibration Values to the actuator. This action will overwrite any existing values stored in hardware.
Load from Hardware will upload the current calibration values stored in the actuator and display them in corresponding Calibration Values tab. Once loaded the Calibrated Pressure value will display the correct calibrated pressure. The uploaded values can then be saved to file for later use.
Save to File. Pressing this button will save the values displayed in each Calibration Values tab to a file. The user will be prompted for a file name prior to saving.
Load from File. Calibration values stored via the Save to File option can be retrieved by pressing this button. The user will be prompted to select a file from a File Open dialog. The loaded data will be displayed in each Calibration Values tab and can be then downloaded to the hardware.