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6) Connect the charging source (Solar, Wind, etc.) positive wire to the controller's INPUT+
terminal. CAUTION: IF THE SOLAR PANELS ARE EXPOSED TO LIGHT, THEY WILL BE
GENERATING POWER. WIND SYSTEMS SPINNING UNCONNECTED CAN HAVE VOLTAGES
ABOVE 100V. It is preferred to stop the generator from turning before connecting the wires from it.
There will be a spark when you attach this wire if the charging source is generating power, this may
be OK if it is not turning very fast but be sure you are not near any flammable fumes. Turn off the
source if possible.
7) DIVERT Feature. When installing a Divert Load, the following steps must also be followed.
You must use a properly sized Divert Load on wind and towed generator systems
a) Connect the Divert Load's negative (-) wire to the negative (-) terminal on the battery or the
system's negative battery bus. If you are using a smart battery fuel meter that measurers total
Input to Output Amp/Hours, it will usually have a shunt in the (-) connection to the battery. Connect
the (-) wire from the Divert Load to the battery (-) not to the shunt as shown in the meter’s manual.
b) Install a fuse rated at 1.5 times larger than your maximum charging current, but less than
30A, in the Divert wire near the controller's terminal block in the Divert Load's positive wire.
Choosing the right Divert Load
The Divert output from the controller is unregulated. This means that when the controller is in Divert
mode, this terminal is directly connected to the charging source, just as if there were no controller
installed. (i.e. The solar panels connected directly to the Divert Load) If the divert load draws less
current than the maximum charging current of your system, the load could burn up. The best rule of
thumb is; either use a Divert Load with a voltage rating twice that of your battery system, or one that
has the same voltage rating as the batteries but has a current rating equal to the maximum your system
can generate. See the Flexcharge Divert loads at www.flexcharge.com
8) CHARGE INDICATOR LIGHT. It is not necessary to use the Charge Indicator Light. If you wish
to use it, connect the CHARGE INDICATOR TERMINAL on the controller's terminal block, to one of
the charging source’s diodes, at the source end. For example; on a solar panel it would connect to
the solar panel end of the diode. See the wiring diagrams. In order to maintain the ultra high
charging efficiencies in the NC25A, it may not be feasible to use the charge indicator while charging
from outboard motors or on certain wind generators. If you have access to the blocking diode in the
charging source or you are charging through a dual battery isolator, then you can use the charge
indicator. A much more informative indication of charging is an amp meter installed into the Red
BAT+ wire anywhere between the controller and the battery.
This concludes the installation section.
If the controller does not function as you think it should, first check the troubleshooting guide in this
manual, then call your dealer, or Flexcharge USA at (231) 547-9430. Web Site www.flexcharge.com
For an explanation of the multi function indicator operation, see the Indicator Function Table on page 7.
Setting the Peak Charge Adjustment Voltage to a new value
WARNING: Mis-adjustment of the controller could seriously damage your batteries over time.
NOTE: The PEAK CHARGE ADJUST was set at the factory to 2.375V per cell (14.25 volts for 12V
systems). All battery voltages are for batteries at 68 degrees F. Peak voltages should be set
higher for colder temperatures and lower for warmer temperatures. The Ideal voltage setting for
Wet Cell Lead Acid and AGM Batteries is 2.39V per cell, (14.35V for 12V systems). The Ideal setting
for Sealed Gel batteries is 2.35V per cell (14.15V for 12V systems). The 2.375V per cell position was
marked with a small indent in-line with the slot in the adjuster. The 2.37V per cell voltage setting works
well with Wet Cell Lead Acid, AGM and Gel battery Technologies. If you move the adjustment and
want to put it back near the original setting, line up the slot as closely as possible with the small indent
(dot) in the case. You should recalibrate the controller if the adjustment is moved.
1) Setting a new regulated voltage, or checking the regulation voltage of your controller.
