Making the DC connections
Two alternative methods for making the DC connections are:
I. connecting the DC positive (+) outputs of the charger to
the battery connections on your battery switches or
2. connecting the DC positive (+) outputs of the charger to
the
output
posts of your battery isolator.
(Do NOT
connect the charger’s outputs to an isolator’s inputs.)
These methods
are
only recommended if your 281 SM will be
mounted much closer to your battery switches or battery
isolator, than it will be to your batteries.
For sample diagrams of these types of installations, refer to
Guest document 1-21681. This is included with all Guest
battery switches and isolators, and is available on request.
1. Use
the following
table to
determine the
gauge
(thickness) of the wire you will need to
carry
the current
from the charger to your batteries safely and efficiently.
Recommended DC wire
sizes
Length of wire, (in feet) as measured from the
battery
charger to the farthest battery
and back to the charger
(maximum 3% voltage drop)
10
l4ga.
l2ga.
lOga.
tOga.
tOga.
6ga.
115
I2ga.
lOgs.
lOga.
Sga.
8ga.
6ga.
6ga.
I
20
10 ga.
10 ga.
8 ga.
6 ga.
6 ga.
6 ga.
4 ga.
25
10 ga.
8 ga.
6 ga.
6 ga.
6 ga.
4 ga.
4 ga.
30
10 ga.
8 ga.
6 ga.
6 ga.
4 ga.
4 ga.
2 ga.
40
8 ga.
6 ga.
6 ga.
4 ga.
4 ga.
2
ga.
2 ga.
50
6 ga.
6 ga.
4 ga.
4 ga.
2 ga.
2 ga.
1 ga.
from Section
E9,
table
Vii
ofthe American Boat
and
YachtCouncil
(ABYC)
standards
and Recommended Practices for 5mail Craft’
2. Find a path for the DC wires between the chargt~rand
your batteries. Remember to route the wires away from
hot surfaces or other areas where the wires could be
damaged. Make sure you will be able
to fasten a ceVble tie
to a solid surface at least every 18 inches throughout the
length of the wires to support them according to ABYC
standard E-9. 1 5h.
-8-
Planning
the DC
connections (cont.)
This is the most common type ofbattery charger installation:
Diagram 2
red
Two 12 volt
batteries
Max.
amps
10 feet
15 feet
20 feet
25 feet
30 feet
--~----
12 volt DC negative
(-)
ground
50 feet
40 feet
8 ga.
-7-
