Send The Deployment Commands; Reviewing The Data; Where' Was The Data; When' Was The Data - RD Instruments WorkHorse User Manual

WorkHorse Mariner ADCP User's Guide
11.5

Send the Deployment Commands

Use WinRiver or VmDas to send the commands to the ADCP.
Things to remember while deploying the ADCP.
12

Reviewing the Data

12.1

'Where' was the Data?

The quickest way to find out the depth of each depth cell is to display your
recorded data using WinADCP. The velocity display tells you the distance
to the center of each cell. The computed distance assumes that the speed of
sound is constant from the transducer to the depth cell. The actual distance
is proportional to the average sound speed; if the average sound speed is 1%
less than the sound speed at the transducer, the distance to the depth cell is
1% less than the displayed distance.
12.2

'When' was the Data?

The time recorded with each data record is the time of the beginning of the
first ping of the ensemble. Plan sets the ping interval so pings occur uni-
formly across the ensemble interval (as opposed to putting all the pings at
the beginning of the interval). It leaves a few seconds at the end of each
ensemble to allow time for data recording. Hence, the average time of the
ensemble is midway between the recorded ensemble time and the time of
the next ensemble.
12.3

'What' is the Data?

The WorkHorse records velocity data in units of mm/s. Calibration depends
on how well the WorkHorse knew the speed of sound (which it computed
based on its measured temperature and the salinity value it was given). A
salinity error of 5 ppt introduces less than 0.5% velocity error.
page 26
2. Apply it thinly and evenly to the transducer faces.
3. Poorly applied coatings on the transducer could adversely
affect instrument performance.
• Magnetic material. Keep the Workhorse's compass away
from magnetic material when you deploy the instrument.
Check for magnetic fields by smoothly moving a compass
around and near the Workhorse and its mounting frame.
• Ping beeps. Whenever the Workhorse pings, an internal
beeper makes an audible beep. The beep consumes negligi-
ble energy and tells you the Workhorse is pinging.
RD Instruments