Kongsberg EM 122, Installation Manual

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EM 122
The system may be delivered in several different versions identified by the “Transmission
x Reception” beamwidth. The standard types are:
• 0.5° x 1° system: 96 TX modules and 16 RX modules
• 1° x 1° system: 48 TX modules and 16 RX modules
• 1° x 2° system: 48 TX modules and 8 RX modules
• 2° x 2° system: 24 TX modules and 8 RX modules
• 2° x 4° system: 24 TX modules and 4 RX modules
The various versions involve different numbers of Transmitter and Receiver boards in
the Transceiver Unit, and different number of transducer modules in the TX and RX
transducer arrays.
Due to Material change for the RX transducer modules, the RX frames are additionally
equipped with baffle plates. The baffle plates are used to deaden noise attenuation on
bottom side of the RX mounting frames.
Transceiver Unit – TRU
The EM 122 Transceiver Unit is a wall-mounted steel cabinet with integrated shock
and vibration absorbers. It holds the circuit boards for transmission, reception and
processing. It is normally located in a “sonar room” close to the transducer arrays. An
Ethernet cable connects the Transceiver Unit to the Operator Station.
The cables from the transducer array's are connected to the Transceiver Unit via the TX
Junction Box(es) and the Preamplifier Unit.
If the system has Sub Bottom Profiler 300, the RX cables are connected via Preamplifier
Unit and up to TRU
Transceiver Unit on page 43
Preamplifier Unit
The EM 122 Preamplifier Unit is a wall-mounted steel cabinet with integrated shock and
vibration absorbers. This unit amplifies and band pass filters the Receive signals from
the RX transducer array. It is installed near the Transceiver unit in the “sonar room”.
The Preamplifier Unit is only used together with the Sub Bottom Profiler 300.
TX Junction Box(es)
TX Junction Box(es) are interface routing box(es) to facilitate the transducer cable
installation.
Each box can handle 24 transducer modules.
317669/B
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