Samlexpower PSE-12125A, Owner'S Manual

Page: 34 / 52

34 | SAMLEX AMERICA INC.
seCtIOn 9 | Installation
- do not use unregulated solar panels to charge a battery. under cold ambient tem-
peratures, the output of the solar panel may exceed 16.5 Vdc. Always use a charge
controller between the solar panel and the battery.
- do not connect to a battery system with a voltage higher than 12 Vdc nominal.
Preventing Reverse Polarity on the input Side
when making battery connection on the input side, make sure that the polarity of bat-
tery connection is correct (connect the Positive of the battery to the Positive terminal of
the inverter and the negative of the battery to the negative terminal of the inverter). If
the input is connected in reverse polarity, fuse(s) on the dc input side will blow and may
also cause permanent damage to the inverter.
connection from the Batteries to the Dc input Side of
the inverter – cable and Fuse Sizes
The flow of electric current in a conductor is opposed by the resistance of the conductor.
The resistance of the conductor is directly proportional to the length of the conductor
and inversely proportional to its cross-section (thickness). The resistance in the conductor
produces undesirable effects of voltage drop and heating. Thus, thicker and shorter con-
ductors are desirable. The size (thickness / cross-section) of the conductors is designated
by Awg (American wire gauge) or in mm
2
.
The dc input circuit is required to handle very large dc currents and hence, the size of
the cables and connectors should be selected to ensure minimum voltage drop between
the battery and the inverter. Thinner cables and loose connections will result in poor
inverter performance and will produce abnormal heating leading to risk of insulation
melt down and fire.
use oil resistant, multi-stranded copper wire cables rated at 105ºc / 194ºf minimum.
do not use aluminium cable as it has higher resistance per unit length. cables can be
bought at a marine / welding supply store.
The cables from the battery to the inverter should be protected by a suitable, very fast
acting dc fuse. use a dc fuse of the appropriate capacity in line with the Positive cable.
The fuse should be within 18” from the battery. class-T or Marine rated battery fuse
(Mrbf) are recommended.
The following size of cables and fuses are recommended. The distance shown is the
distance between the battery and the inverter. The recommended size of the cables will
limit the voltage drop up to 3% (The length of the cable for calculating the voltage drop
has been taken as 2 times the distance between the inverter and the battery because volt-
age drop occurs due to the resistance of the Positive and negative cables.