B&G HS2000 - Manual (Page 8)

HS 2000 User Manual
Part 1 - Introduction
HB-0846-03
1-4
The Main Processor Unit contains the battery backed memory that
stores all calibration, damping and alarm settings while the power
is OFF; these are adjustable from any FFD.
1.3 SENSORS
1.3.1 Paddle-Wheel
The Paddle-Wheel Speed Sensor is designed primarily for cruising
boats and consists of a paddle-wheel which protrudes through the
hull via a hull-housing. So that the paddle-wheel may be cleaned
at regular intervals, the housing is provided with a flap valve which
closes automatically when the unit is withdrawn into the boat.
1.3.2 XTL Fin Sonic Transducers
The XTL Sonic Speed
?
Transducer provides an accurate and safe
measurement of speed, distance travelled and depth, essential for
basic navigation and dead reckoning.
The XTL Sonic Speed
?
System operates on the Doppler principle
by measuring the speed of water travelling between the two Sonic
Speed Transducers and comparing the signals in the XTL
Microsonic control box. Display of linear speed readings up to 35
knots and accurate, stable depth information at high speed,
ensure safety in all depths of water.
The single, one piece transducer is bolted to the bottom of the
boat and has minimal protrusion inside the boat. The one piece
transducer is hydrodynamically designed to offer minimum drag
and if damaged does not threaten the water-tight integrity of the
boat.
Fig 1.2 XTL Fin Sonic Transducers