ROGUE MPT-3024, Инструкция по установке и руководство пользователя

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4. System Design Considerations
Whether you are planning and installing your energy system for the first time
or retrofitting an existing system, you’ll obtain the best performance if you
follow a few simple guidelines.
4.1 Minimize the distance of wire runs
Place the PV array and battery bank as close as practical to the MPT-3024.
This will limit the power loss associated with long wire runs. Longer lengths of
wire will cause an increase in power loss, especially at higher currents. See
Table 4.1.1 to determine the resistance of selected wire gauges versus wire
length.
4.2 Maximize wire size
The wire used to connect the PV array and battery bank to the MPT-3024
should be of a heavy enough gauge so as not to introduce excessive voltage
drops and/or current limitations. At higher currents, light gauge wire may
introduce a large voltage drop from the PV array, causing an extreme loss of
power and erratic operation of the MPT-3024. Wire of insufficient size may
also constrain charging current to the battery (which is charging at a relatively
constant voltage at any given point in time). The effects of wire size may not
be evident at lower charging currents; they may gradually appear and get
worse as current increases.
Table 4.1.1. Copper wire resistance and power loss versus wire gauge.
Wire Gauge
(copper)
Resistance
(ohms/ft at 25
o
C)
Power Loss @ 30A (watts/
ft)
#12 0.00162 1.46
#10 0.00102 0.92
#8 0.00064 0.58
#6 0.00040 0.36
#4 0.00025 0.23
#2 0.00016 0.14