||An acoustic current meter designed to measure high-resolution water velocity and pressure data in marine environments. It is used for studies of turbulence, waves, bottom boundary layers, ocean engineering, coasts and rivers. The Vector 3D outputs Doppler velocity, temperature, pressure, tilt, and heading measurements, and uses the principle of Doppler shift to measure current velocity. It supports real-time or burst sampling methods to preserve battery power. An optional motion sensor (Attitude and Heading Reference System, AHRS) with a faster response time can be used in place of the standard magentometer, heading and tilt sensors. The AHRS is useful for studying the motion of the Vector itself, allowing improved separation of Vector motion from velocity measurements. The Vector 3D measures veolcity over the range +/- 0.01 to 7 m/s with an accuracy +/- 0.5 % of measured value +/- 1 mm/s. It measures temperature over the range -4 to +40 degC with an accuracy of 0.1 degC and resolution of 0.01 degC. It has a sampling rate of 1 to 64 Hz, a battery capacity of 100 Wh and is depth-rated to 300 m.