1. Disconnect all AC and DC power
Before starting, disconnect the main positive cable from all batteries to
eliminate the possibility of a short circuit while installing the distribution
panel. Also disconnect the AC shore power cord from the boat to
eliminate the possibility of electrocution from AC wiring in the proximity
of the DC distribution panel.
2. Select mounting location and cut opening
Select a mounting location which is not in an area where fl ammable
vapors from propane, gasoline or lead acid batteries accumulate. This
panel is not ignition protected and may ignite such vapors.
Using the panel template provided, make a cut out in the mounting
surface where the distribution panel is to be mounted. Do not yet
fasten the panel to the mounting surface.
3. Select positive feed wire
Determine the positive feed (red) wire size by calculating the totalamperage of the circuit that will be routed through the panel. The
positive feed wire must be sized for 3% voltage drop at the panel rating
(amperage rating) or the maximum amperage that will be routed
through the panel in any particular installation, whichever is less. It is
recommended that the positive feed wire be sized for the full panel
capacity, which, in most cases, will require at least 10 AWG wire,
assuming a 10 foot wire run between the panel and the batteries in
12 volt systems. Refer to the Wire Sizing Chart for other situations.
Remember that the length of the circuit is the total of the positive wire
from the power source to the device and the negative wire back to the
DC Negative Bus. Be certain that there is a fuse or circuit breaker of
the correct size protecting the positive feed wire.
4. Install LED negative feed wire
Use a 16 AWG wire to connect the LED negative feed (brass) terminal
on the back of the switch to the DC Negative Bus.
5. Install bilge pump circuit wires
Determine the proper wire size for the bilge pump and fl oat switch using
the guidelines in step 3. Verify that the standard 15 amp fuse installed in
the panel is appropriate for both the circuit wire and the bilge pump.
Remove and replace with the bilge pump manufacturers recommended
fuse size (20 amp maximum). Connect the fl oat switch to the bilge pump
and in accordance with the manufacturers instructions. As illustrated in
the wiring diagram below, connect the positive (red) wire from the fl oat
switch to the switch terminal marked “Float” and the positive (red) wire
from the bilge pump to the switch terminal marked “Pump”. Connect the
bilge pump negative (yellow or black) wire to a DC negative bus such as
Blue Sea Systems’ MiniBus PN 2304.
6. Mount panel with water resistant gasket
A gasket has been included for sealing the panel against the mounting
surface. The gasket will easily stretch around the panel when applied
from the front. Place the gasket between the panel and the mounting
surface. Make sure all surfaces are clean and free from debris. Using
the panel mounting screws supplied with the panel, screw down the
panel to the mounting surface.
Reconnect the main positive cable to the battery terminals and turn the
main switch on to supply power to the panel. Turn on the bilge pump
and test the voltage at the panel. Compare this voltage to the battery
terminal voltage to determine that the voltage drop is within 3%.
This Blue Sea Systems water resistant power distribution panel is
furnished with a 15 amp AGC (fast acting) glass fuse. This rating will not
be appropriate for all bilge pumps. Remove and replace with the bilge
pump manufacturers recommended fuse size (20 amp maximum).
Failure to properly fuse your bilge pump is dangerous and may void the
• American Boat and Yacht Council (ABYC) Standards and Recommended
Practices for Small Craft sections: E-9.
• United States Coast Guard Code of Federal Regulations