Table 38: Velocity Data Format - Teledyne WORKHORSE Operation Manual

May 2015
The H-ADCP packs velocity data for each depth cell of each beam into a two-byte, two's-complement inte-
ger [-32768, 32767] with the LSB sent first. The H-ADCP scales velocity data in millimeters per second
(mm/s). A value of –32768 (8000h) indicates bad velocity values.
All velocities are relative based on a stationary instrument. To obtain absolute velocities, algebraically re-
move the velocity of the instrument. For example,
RELATIVE WATER CURRENT VELOCITY:
INSTRUMENT VELOCITY
ABSOLUTE WATER VELOCITY
The setting of the EX-command (Coordinate Transformation) determines how the H-ADCP references the
velocity data as shown below.
EX-CMD COORD SYS
EX00xxx BEAM
EX01xxx INST
EX10xxx SHIP
EX11xxx EARTH
Positive values indicate water movement toward the H-ADCP.
Table 38: Velocity Data Format
Hex Digit Binary Byte
1-4 1,2
5-8 3,4
9-12 5,6
13-16 7,8
17-20 9,10
21-2052 11-1026
Page 214
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
EAST 650 mm/s
: (-) EAST 600 mm/s
: EAST 50 mm/s
VEL 1 VEL 2
TO BEAM 1 TO BEAM 2
X AXIS Y AXIS
X AXIS Y AXIS
EAST NORTH
Field Description
Velocity ID Stores the velocity data identification word (00 01h).
Depth Cell 1, Veloci- Stores velocity data for depth cell #1, velocity 1. See above.
ty 1
Depth Cell 1, Veloci- Stores velocity data for depth cell #1, velocity 2. See above.
ty 2
Depth Cell 1, Veloci- Stores velocity data for depth cell #1, velocity 3. See above.
ty 3
Depth Cell 1, Veloci- Stores velocity data for depth cell #1, velocity 4. See above.
ty 4
Cells 2 – 128 (if used) These fields store the velocity data for depth cells 2 through 128 (depending on the
setting of the WN-command). These fields follow the same format as listed above for
depth cell 1.
WorkHorse H-ADCP Operation Manual
VEL 3 VEL 4
TO BEAM 3 0
0 ERROR VEL
VERTICAL ERROR VEL (tilt applied)
VERTICAL ERROR VEL (heading applied)