Instruction Manual

Troubleshooting
5–2 975-0400-01-01 Revision H
This manual is for use by qualified personnel only.
PV Charge Control Troubleshooting
Table 5-1 lists possible problems that may arise when using the Conext MPPT
Solar Charge Controller (solar charge controller).
Table 5 - 1 PV Charge Control Problems
Problem Possible Cause Solution
The LCD shows “Low
Light” under all
conditions.
PV wires are connected
in reverse polarity.
The PV input has short
circuited and input
voltage is zero volts.
Verify PV polarity relative
to battery negative.
Low panel output. Input
and output voltages read
about the same.
Array maximum power
point is less than the
nominal battery voltage.
The solar charge
controller is still
charging, but cannot
charge at V
MPP
Check or reconfigure the
array.
Uneven output current
between multiple solar
charge controllers.
A. Solar arrays are
supplying different
amounts of current to
each charge controller.
B. Charging set points
are not all set the same.
C. Excess voltage drop
in wiring causing
controllers to measure
the battery voltage
differently and regulate
accordingly.
D. Chargers are in
Constant Voltage
(absorption) mode and
therefore are limiting
their output current to
maintain the present
battery voltage. In this
situation, some units will
produce more output
current than others.
A. Check array output,
but consider that this
could be a normal
operating condition if the
arrays are located in
different locations and/or
point in different
directions.
B. Set controllers to the
same settings.
C. Check wiring.
Upgrading or shortening
the wire run may be
required.
D. No need for
intervention, as this is a
normal operating
condition.