Eagle Electronics SeaFinder 480DF - Manual (Page 31)

25
attach the power cable directly to the battery. You can attach the power
cable to an accessory or power buss, however you may have problems
with electrical interference. Therefore, it's safer to go ahead and attach
the power cable directly to the battery.
CAUTION:
When using the unit in a saltwater environment, we strongly
recommend that you shut off the power supply to the power cable
when the unit is not in use. When the unit is turned off but still
connected to a power supply, electrolysis can occur in the power
cable plug. This may result in corrosion of the plug body along with
the electrical contacts in the cable and the unit's power socket.
In saltwater environments we recommend you connect the power
cable to the auxiliary power switch included in most boat designs.
If that results in electrical interference, or if such a switch is not
available, we recommend connecting direct to the battery and
installing an inline switch. This will let you shut off power to the
power cable when the unit is not in use. When you are not using
the unit, you should always shut off power to the power cable,
especially when the power cable is disconnected from the unit.
If possible, keep the power cable away from other boat wiring,
especially the engine's wires. This will provide the best isolation from
electrical noise. If the cable is not long enough, splice #18 gauge wire
onto it. The power cable has two wires, red and black. Red is the
positive lead, black is negative or ground. Make sure to attach the in-
line fuse holder to the red lead as close to the power source as possible.
For example, if you have to extend the power cable to the battery or
power buss, attach one end of the fuse holder directly to the battery or
power buss. This will protect both the unit and the power cable in the
event of a short. It uses a 3-amp fuse.