Scaling is an important tool when performing a calibration and/or correlating two or more values. Most of the time, a process measurement is compared against a known measurement (the standard) When you need to scale the SRV measurements to match the standard or reference laboratory value, use the “Scaling” Rheonics Control Panel function.

1.1. Open RCP and go to the “Scaling” tab (This requires to enable expert mode), there open the “Select Measurement” and select the desired measure to scale.

Figure 1. Select Measurement tab options

1.2. When a parameter is selected, the software is going to automatically populate the unscaled value and scaled values.

Figure 2. Viscosity selected, the unscaled and scaled values are displayed in the screen

1.3. Select the scaling method, “Single Point” for offset calibration should be used when either the measurements range is kept around a narrow value, or when the sensor response and the ideal response maintain the same behavior within the sensor operation range or “Two Point” for offset and slope scaling when the sensor works in a wide range of measurements and the difference between the ideal response and the sensor response changes linearly within that range. 

Figure 3. Scaling methods

2. Single point calibration(Offset)

2.1. After selecting the “Single Point Scaling”, click in the read button, this will populate the “Sensor Read Out” box with the raw value currently being measured by the sensor. 

Figure 4. Click-in Sensor Read Out and populate

2.2. Save the read parameter (Sample 1) by click-in in the button “set”  

Figure 5. Saving Sample 1 by click-in set button

2.3. Write the “expected value” for the measurement, for the offset calibration this means that the sensor output is higher or lower than the expected reference value. Click “Write” to store the value in SMET. 

 Figure 6. Saving lab value 1 of the expected value.

2.4. Click “SCALE” to use the stored samples to scale the SMET output. In this example notice that the software automatically shows the value that fix the parameter to the closest value to the desired value.

Figure 7.  SCALE BUTTON to load the stored samples, we noticed the closest value to fix the expected value.

2.5. Read the Scaling Coefficients

3.1. After selecting the “Two Point Scaling”, click in the read button, this will populate the “Sensor Read Out” box with the correct raw value and save these values. Click “Set” Button

Figure 8. Saving Sample 1 by click-in set button in Two-point Scaling

3.2. To write values click “Write Button” with the laboratory parameter.

Figure 9. Click to save LabValues in Two-point Scaling

3.3. Following the same steps in the single point calibration repeat and fill all the parameters as desired. For this example, the scaling will 100x the actual viscosity.

Figure 10. Scaling 100x the current viscosity value.

3.4. The two-point calibration allows offset and slope calibration, below find an example with this. In this example, the Scaled value will be 84x the viscosity with an offset of 20.

Figure 11. Scaling of both offset and slope.

Resources:

Theory behind scaling: https://support.rheonics.com/support/solutions/articles/81000391533-scaling-sme-parameters

To enable expert mode: https://support.rheonics.com/support/solutions/articles/81000289485-set-density-input-to-srv-inline-viscometer-for-dynamic-viscosity-and-kinematic-viscosity-outputs

How to do Scaling Video!