Geometrics G-877, Руководство по эксплуатации

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or NT, 2000 or latest Microsoft offering installed. Note that the Logging Computer should have
two serial communication ports (one for magnetometer and one for GPS). This is not an issue
with Desktop computers which come with 2 com ports as standard issue. However, with
Notebooks or Laptops, a second port must be added. This may be either PCMCIA or USB serial
port add-on made by Socket I/O or Entrega. Contact Geometrics for more information if you are
unclear about how to increase your computer port capacity.
2.3 SYSTEM INSTALLATION
Begin by installing the Logging and Display Computer (which may include printer) and G–877
AC Power Supply in the instrument room and connect them to 115/220VAC 50/60 Hz power. If
DC power is used, connect the Junction Box to a source of 24-32 VDC (such as two 12 Volt
batteries in series) with the supplied DC power cable. If you are using DC power be sure to
connect the Red Clamp to positive and the Black Clamp to negative terminals on the batteries. If
used, connect the printer to the computer with a printer cable (that comes with the printer) and
load the paper. Connect the computer to the Junction Box with the Serial 9 pin cable. Mount the
GPS antenna in an appropriate position and run the serial cable from the GPS console to one of
the serial ports on the computer. Note the X and Y position of the GPS antenna relative to the
G–877 tow cable tow point on the rear of the ship. This information will be needed later when
we input the offset of the antenna to the Magnetometer Fish into
MagLogLite

.
Unpack the tow cable and magnetometer fish. As shipped the tow cable should already be
connected to the magnetometer fish. If the tow cable is not connected to the fish or there is need
to disconnect it, see Appendix B for instructions. For testing purposes, place the fish on a
cardboard box or other non-magnetic surface (watch out for nails in wooden crates, at close
distances they will interfere with mag operation). Connect the other end of the tow system to the
Junction Box or to On-Board as noted below.
The basic G–877 system uses a single tow cable from Fish to Junction Box because the standard
tow cable (60m or 200 ft) is easily managed by hand. However if longer cables are used (up to a
maximum of 400m or 1312 ft), a winch will probably be required. In this case, Geometrics can
supply an optional waterproof On-Board Cable (100 or 200 ft – 30m or 60m) that runs from the
winch to the Junction Box. Since the winch is in a wet environment, we supply the G–877 Tow
Cable and the On-Board Cable with rubber marine connectors (8 pin Subconn) for water
environment connection similar to the connectors used on the tow cable to magnetometer fish
connection. If the on-board cable is used, on the Junction Box end we supply an 8 pin Subconn
to 5 pin Bendix adaptor cable to connect the On-Board Cable to the Junction Box. Contact the
factory for more information if you wish to use longer tow cables.
Connect either the Tow Cable or On-Board Cable to the Junction Box. Connect the On-Board
cable to the tow system if On-Board is used. Tie off the or otherwise secure the tow system to
the vessel structure and set the Magnetometer Fish on a non-magnetic surface for testing
purposes. It must be several meters from steel objects like deck, winch, engines etc., and
preferably farther.
G–877 MARINE MAGNETOMETER OPERATION MANUAL
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