Outback FM80 User Manual

Operation
24 900-0009-01-00 Rev D
EX-Absorb
There is an external DC source other than PV keeping the battery above the Absorbing voltage
set point. The FLEXmax will stop charging because it is not needed.
Floating
The FLEXmax is in the Float stage of a three-stage cycle, regulating the battery voltage at the
Float voltage set point. This stage is temperature compensated. (See page 99.) If the battery
voltage drops below the Float voltage, the FLEXmax will employ the MPPT function to draw
more power from the PV array. (This may occur if the batteries are powering loads.) If this
happens, the operating mode will change to MPPT Float. (See below.)
GT Mode
The FLEXmax is in Grid-Tie mode. In a system with an OutBack grid-interactive inverter, a
HUB, and a system display, the FLEXmax will display GT Mode, if and only if, the inverter is in
Sell mode and the FLEXmax is in the MPPT BULK or MPPT FLOAT modes. This message
also indicates that Grid-Tie mode communication has been established between the inverter
and charge controller. GT must be selected in the MPPT Mode advanced menu in order to be
viewed. (See page 50.)
High V
oc
This indicates the PV array’s open-circuit voltage is too high for the controller to safely operate
(> 145 Vdc). This should only occur with systems using 72 Vdc nominal PV arrays in very cold
temperatures (below –15°C / 5°F). The FLEXmax will automatically restart operation once the
PV array’s open-circuit voltage falls to a safe level (145 Vdc or lower).
CAUTION: Equipment Damage
Voltages in excess of 150 Vdc are likely to damage the FLEXmax controller. The PV array
should be designed to avoid ever reaching these voltages.
Low Light or Snoozing
A Low Light or Snoozing mode indicates that the PV voltage is high enough to activate the
FLEXmax, but there is not enough current available to charge. During the initial tracking (see
Wakeup and Tracking), if it is determined to be too late (or too early) in the day, the FLEXmax
will display Low Light for a few seconds and then display Snoozing for five minutes (default).
This reduces energy usage and unnecessary powering of the FLEXmax. This message is also
displayed in extremely cloudy weather.
MPPT Bulk
This is a Maximum Power Point Tracking mode which harvests the maximum wattage available
from the PV array. The controller is trying to regulate the battery voltage towards the
Absorbing voltage set point. Normally the charge controller enters this mode at the beginning
of the day or when a new charge cycle begins. The controller may also enter this stage if there
is not enough PV energy to maintain a different stage, such as Absorbing. See page 22 for
more information.