September
2017
Sentinel V SC and RT Operation Manual
Page 94
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
Maintenance Schedule
To ensure that you continue to receive optimal results from your Teledyne RD Instruments product(s),
TRDI recommends that every Sentinel V ADCP be returned to our factory for an inspection every two to
three years. We’ll provide your unit with a thorough multi-point inspection, and let you know if any refur-
bishment services are required to properly maintain the unit. To learn more about this service, please
Calibration Items
Use the following calibration schedule:
Item
TRDI Recommended Period
Transducer Beam Angle
TRDI recommends return every two to three years for verification of velocity
accuracy
Pitch & Roll (Tilt)
TRDI recommends return every two to three years for Factory calibration
Temperature (Factory)
Pressure Sensor (Factory)
Heading (Factory)
Heading (Field Pre-Deploy)
Field Compass Calibration performed prior to each deployment (see
Heading (Field Post-Deploy)
Pressure sensor and compass drift effects will accumulate over time. TRDI recommends a
factory calibration be done every two to three years. The longer you wait between factory
calibrations, the more error (due to drift) you can expect to have.
For example, the pressure sensor has an initial accuracy spec of ±0.25%, and a long-term drift
spec of ±0.11%. Most of the 0.11% drift will occur in the first 12 months of operation. The
fluxgate compasses accumulate an error of approximately 1% over a year.
