User's Manual

INSTALLATION
FIXED STATIONS
374 ENVOY™ TRANSCEIVER REFERENCE MANUAL
Protecting the cables
Physical protection
Protect all the cables from sharp edges and mechanical abrasions. Cables that pass
through panels or walls must be protected by grommets. Such holes need only be large
enough to allow the end of the cable with the smaller connector to pass through.
Removing a connector should be a last resort. Externally, the cable and connectors
need to be weatherproofed using self-amalgamating rubber tape.
CAUTION: Removal of factory-fitted connectors may cause cable or connector
faults.
CAUTION: Crimp-style coaxial connectors for vehicle installations should be
avoided because they are susceptible to mechanical damage and are not
weatherproofed.
NOTE: Any cabling under carpet or floor mats should be clear of foot traffic.
Electrical protection
The transceiver is provided with adequate internal protection. The transceiver supply
is also fitted with adequate protection.
If a battery is used, Codan recommends that a suitable cartridge fuse (32 A, Codan
part number 15-00711) is fitted in the positive wire, close to the battery. This protects
the power cable from risk of fire if damaged insulation should touch surrounding
metalwork.
As the fuse is not included to protect the transceiver circuits, it should be of large
physical and electrical size to eliminate the possibility of voltage drops across the
fuse.
WARNING: Do not use normal glass in-line automotive fuses.
Earthing the transceiver in a fixed station
A good RF earth is essential for efficient operation of the fixed station. The transceiver
chassis should be connected to earth via the earth screw on the rear panel of the
transceiver. Use a copper braid of at least 12 mm (½ in) width to connect the
transceiver to the earthing point.
NOTE: Keep the earth braid as short as possible.
All individual units in a fixed station should be earthed to prevent RF interference
corrupting the data and audio circuits. Equipment that requires earthing has an earth
screw fitted. To achieve good earthing, connect separate earth braids to the earth
screws on each piece of equipment and connect them back to the same earthing point.
NOTE: Ideally, all earth braids should connect directly back to a single point
to prevent earth loops.