Pre-measurement Tests in TRDI SxS Pro

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In this video, we will highlight the necessary pre-measurement tests as part of a midsection ADCP measurement in TRDI SxS Pro. Note: Use of trade names is for descriptive purposes only, and does not imply endorsement by the USGS. For additional videos in this series, visit the following link:


Date Taken:

Length: 00:02:45

Location Taken: Augusta, ME, US


Hi, my name is Nick Stasulis and I am a hydrologic technician with the Maine Office of the New England Water Science Center. In this video, we will highlight the necessary pre-measurement tests as part of a midsection ADCP measurement in TRDI SxS Pro.

After setting up your new measurement in the wizard, start by setting the ADCP’s clock by selecting Acquire > Set ADCP Clock. Next run the ADCP test by selecting Tests > ADCP Tests. Before starting a test ensure the ADCP is in calm water, if possible. Click Run Tests and you will notice the dialog will start showing information and display a number of pass or fails, here. The number of tests run will vary with instrument. If there are failures, try moving the ADCP to a different location and running the test again. If there are repeated failures, collect data while looking for irregularities and be sure to follow up with an experienced user or the manufacturer.

Unless the ADCP compass is disabled, such as for an ice measurement, calibrating the compass is recommended. Calibrating the ADCP’s compass is recommended as the compass is being used to account for boat rotation so the velocity data can be oriented properly. Also, having a properly calibrated compass can be useful to determine heading of the ADCP during data collection.

The calibration is conducted by selecting Compass Calibration from the Tests menu. Versions of SxS Pro 1.15 or later will allow calibration of all TRDI ADCPs. For a Rio Grande, be sure you select calibrate, then evaluate. With the StreamPro, RiverPro, new RiverRay and RioPro compass, you will be prompted to conduct the evaluation once the calibration is complete. Specifics on calibrating all TRDI compasses can be found in the WinRiver II user’s guide.

The last important check on the ADCP is to perform a water temperature check. First, start the instrument pinging by pressing F4. Use an independent thermistor to obtain a water temperature reading right next to the ADCP, and note this reading and the reading from the ADCP in the Temperature/Salinity Readings page in your staged mid-section channel measurement notes using SVMobile. The ADCP temperature is easily obtained here. These readings should be within 2 degrees Celsius before you begin data collection. The StreamPro can take a particularly long time to equilibrate, so make sure this comparison is done before collecting any data.

To be clear, since bottom tracking is not being used, midsection ADCP measurements do not require moving bed tests.