Installation And Operation - Samlex Solar SCC-30AB Owner's Manual

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InstallatIon & operatIon
Warning!
• This unit will be damaged if the battery is connected in reverse polarity.
• ENSURE that the battery + and - wires are correctly connected before proceeding.
• Damage due to reverse battery connection is not covered under warranty!
• When connecting the battery, connect the battery Negative first & then the battery Positive.
• When disconnecting the battery, disconnect battery Positive first & then battery Negative.
Installation Steps
Wire Sizing – Solar Panel to Controller and Controller to the Battery
Warning!
Wires have resistance – thinner and longer wires have higher resistance. Current
flowing through resistance produces voltage drop and heating resulting in power loss
(as heat) and reduced system efficiency. Higher current produces higher voltage drop
and higher heating. Overheating also results in deterioration of wire insulation and
consequent possibility of fire due to short circuit. Further, higher wiring resistance
reduces current flow resulting in higher charging times. Voltage drop in the wiring
from the Charge Controller to the battery results in undercharging and consequent
sulfation, loss of capacity and premature battery failure. It is, therefore, recommended
that thicker wire size should be used to limit voltage drop to 3% or lower.
Size of wiring is designated by AWG (American Wire Gauge) #. For AWG numbers up
to AWG # 1, the smaller the AWG number, the thicker the size of conductor. Size of
wiring for a particular application will depend upon the following:
(a) The maximum current it is allowed to carry (called Ampacity) at specified
temperature of the conductor / insulation and
(b) The permissible voltage drop across the distance over which this current is carried.
The size of conductors should be determined based on (i) Ampacity and (ii)
maximum voltage drop of 3% for current = the Short Circuit Current Isc of the
Solar Panel / Array (thicker of (i) & (ii) should be chosen). The wires should be
multi-stranded insulated copper rated for at least 105ºC.
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