OutBack Power Owner's Manual

Troubleshooting
56 900-0209-01-00 Rev B
Table 7 Troubleshooting
Symptom Remedy
Unit not operating;
unit had worked
normally before;
normal light
conditions

Check the charging stage. Check other controllers (if presen
t). If the batteries are
near
ly charged, one controller may taper off (in the Absorption or Float stage) wh
ile
the other(s) complete the charge.

High temperature fault. Check controller temperature (see page 38).
T
he FLEXmax 100 will stop functioning at an
Output FETs
reading of 90°C.
The system display
Over Temperature
error will indicate
Y
. (See page 38.
)

High
V
oc
fault. Check PV array voltage. If the open-circuit voltage (V
oc
) is too
hig
h, the controller cannot safely operate. The system display
VOC Too High
error
w
ill indicate
Y
. (See page 38.) The FLEXmax 100 will automatically restar
t
oper
ation once the V
oc
decreases to a safe level.
Upp
er limits: 24-volt system = 275 Vdc, 36-volt system = 283 Vdc, 48-volt system =
290 Vdc. See page 66 for more information.
CAUTION: Hazard to Equipment
Voltages in excess of 300 Vdc are likely to damage the FLEXmax 100.
The PV array should be designed to avoid ever reaching these voltages.
Unit not producing
expected power

Check PV and battery voltages. If they are varying widely, the controller may
be in
the process of
an MPPT sweep. It should settle on a stable power point an
d
prod
uce normally again after a
short time.

Check PV conditions. Clouds, shading, or dirty modules cause poor performanc
e.

Check battery conditions and charging stage. If the batteries are charged (i
f the
control
ler is in the Absorbing or Float stage), the controller will produce only enoug
h
po
wer to regulate the voltage at those set points. Less power is required.

Determine the specified short-circuit current of the PV array. T
he MPP current is
related to this number. Use a multimeter to determin
e if the short-circui
t current is in
the e
xpected range. Array or wiring problems may restrict the available powe
r.

Check the PV array temperature. At high temperatures, the maximum power po
int
voltag
e may be near or lower than the battery
voltage.

Check FLEXmax 100 external temperature. The output is derated above ambien
t
temperatur
es of 25°C (77°F). Also check FLEXmax 100 internal temperature usi
ng
the system display. See page 38.
If a temperature reading is greater than 142°C or less than -40°C, a sensor may
have failed. The
Reduced Performance
error will show
Y
(see page 38).
NOTE
:
If the temperature is high, check the condition of the heatsink. This may
require dismounting the controller. If the heatsink is blocked with mud, organ
ic
material, etc., the contro
ller will not receive normal ventilation. Clean it by scrapi
ng
bet
ween the fins with a thin wooden stick. Spraying is not recommende
d.
Unit in equalization
cycle but not
achieving expected
results

Check equalization settings using the system display. (See pages 44 and 68). T
he
defau
lt settings are not sufficient for many batteries and may need to be adjusted.

The cycle will begin when the
Equalization Voltage
set point has been reache
d. A
small arra
y or cloudy weather will delay the equalization cycle. Running too many
battery loads will also delay the cycle. Loads should be removed or minimi
zed.

Check the PV array temperature. At high temperatures, the maximum power po
int
voltag
e may be near or lower than the battery voltage. This can delay the cycle.
Battery Calibration
setting does not
respond
The system display will not report this setting if remote battery sensing is connected.
To test this function, temporarily disconnect remote battery sensing. (See page 21.)