1. Setting limits on the RCP
Below find how to configure the communication channels on the sensor, also the useful tools RCP provides
2. 4-20mA Settings
2.1. This box allows the reads and sets the upper and lower limits for each 4-20 mA measurement channel.
Figure 1. 4-20mA settings box
2.2. Open the dropdown list and select the parameter to measure. The parameters available to be selected are as following:
- Kinematic Viscosity
- Calculated Viscosity
- Calculated Density
Figure 2. Selecting parameter in dropdown list
2.3. To change the upper and lower limits, follow the next steps:
2.3.1. Enter the lower limit on the box labeled “4 mA”.
2.3.2. Write the upper limit on the box labeled “20 mA”.
2.3.3. Click the “Update” button to send the new values to the SME. If the write operation succeeds, the “Write” button will turn green for a few seconds. Otherwise, will turn red and the boxes will go back to the previous values.
Figure 3. Updated limit
3. Performing calibration
3.1. The SME has three 4-20 mA channels to output measured Viscosity, Density, and Temperature. Each channel can be calibrated individually. To calibrate one channel (ch1 for example) follow these steps:
3.1.1. Attach a current measurement instrument to measure the current on channel 1, attach between -gnd and ch1. Ensure the instrument has a measurement accuracy better than desired accuracy. By default, the channels are factory calibrated to better than 1% absolute accuracy
3.1.2. Click the “4 mA” button, under the “channel 1” label. This will output a 4 mA current through ch1. The 4 mA button will turn green to indicate that the SME is in “4mA mode”
Figure 4. Low limit check.
3.1.3. Register the value measured with the milliammeter in the box above the 4 mA button.
Figure 5. Measured parameter for channel 1
3.1.4. Repeat the same process for Click the “16 mA” button, under Channel 1 tag to output a 16 mA current through channel 1. The 16 mA button will turn green to indicate that the SME is in 16 mA mode. Also, the 4 mA button will go back to gray color, since the SME is no longer in that state.
Figure 6. Upper limit check
3.5. Register the measured value in the box above the 16 mA button.
Figure 7. Measured parameter for channel 2
3.6. Click the “Calibrate” button to send the measured values to the SME. If the command was correct, the button will turn green for two seconds and go back to gray, to indicate that the SME is in measurement mode.
Figure 8. Calibration complete.
4. Calibration Check
4.1. To verify the calibration, click on the “Test: 10 mA” button, to output a calibrated 10 mA current through the channel. The button will remain green until you press it again, and then the system will go back to measurements mode.
Figure 9. Calibration Check