Kongsberg EM 710, Installation Manual

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EM 710
2.2 System characteristics
Main units
The basic EM 710 multibeam echo sounder consists four units
• Transmit Transducer
• Receive Transducer
• Transceiver Unit
• Operator Station
A complete mapping system will in addition include a vessel
motion sensor, heading sensor, sound velocity sensor(s) and a
positioning system.
Transducers
The EM 710 transducers are fully water tight units intended for
many years of trouble-free operation in rough seas. The transmit
and receive transducers both have a width of 224 mm and a height
of 118 mm. Their length depends upon the chosen beamwidth,
either 970 mm for a 1 degree unit or 490 mm for a 2 degrees unit.
The weights are respectively 35 and 18 kg (excluding cables).
The weight of a 0.5º x 1º system are 70 and 18 kg (excluding
cables).
The transducers have a maximum depth rating of 250 m.
A transmit beamwidth of 0.5 degree is achieved by mounting
two 970 mm transmit transducers together alongship. Such a
beamwidth reduction is not possible with the receive transducer.
The transducers are supplied as standard with 15 m long
underwater cables terminated with a surface connector directly
pluggable into the Transceiver Unit. On special order underwater
connectors or longer cables may be supplied. Five, ten or twenty
cables are used on the transmit transducer, two or four on the
receive transducer, in accordance with the transducer length.
Transceiver Unit
The EM 710 Transceiver Unit contains all transmit and receive
electronics, and the Processing Unit which performs the
beamforming, bottom detection, and motion and sound speed
corrections. It contains all interfaces for time-critical external
sensors such as vessel attitude (roll, pitch, heading and heave),
vessel position and external clock. More than one sensor of each
type may be connected simultaneously, with one in use but all
logged.
The Transceiver Unit comprises two 19” sub-racks contained in a
cabinet designed for bulkhead or deck mounting.
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