Installation
26
900-0209-01-00 Rev A
Power Up
To power up the controller:
1. Connect battery power to the controller by closing the disconnect.
2. Connect PV power to the controller by closing the disconnect. See
Initial Operation
on page 27.
The FLEXmax 100 uses power from the battery bank to operate. The battery voltage must be at least
15 volts or higher to power up the charge controller.
When battery power is detected, the charge controller will flash all LED indicators in sequence as it
performs a self-test.
The blue
CHARGING
indicator will then flash to show the nominal system voltage that was detected.
Beginning with a 24-volt system, each flash indicates an increment of 12 volts. (Two flashes = 24 Vdc,
three flashes = 36 Vdc, and so on.)
See page 29 for descriptions of all LED indicators.
IMPORTANT:
The PV array voltage is automatically detected upon connection. The PV array voltage must
never exceed 300 V
oc
.
NOTE:
The charge controller automatically senses the nominal battery voltage upon
connection. Once set, it retains the nominal voltage setting. Following any type of
shutdown or disconnect, it will return to operation automatically.
The FLEXmax 100 should be restored to factory default settings (see page 50) and the
nominal voltage should be reset (see below) any time the system is substantially
revised or the controller is relocated.
Setting the Nominal Voltage
Upon initial power-up, the FLEXmax 100 will sense the battery voltage and use this reading to determine
the nominal system voltage — a battery bank that is nominally between 24 and 48 volts DC.
The batteries must be within the appropriate voltage range for the controller to take the correct reading.
A severely discharged 48-volt battery bank, for example, could read as a 36-volt bank and cause the
controller to charge inappropriately (or not at all).
The ranges of detection for each nominal battery voltage are:
24-volt system — above 15.7 Vdc to 31.4 Vdc
36-volt system — above 31.4 Vdc to 43.2 Vdc
48-volt system — above 43.2 Vdc to 62.8 Vdc
Normally the nominal system voltage is retained. If the FLEXmax 100 is disconnected from the batteries
or otherwise loses power, upon a new power-up it will continue using the nominal voltage and settings
determined previously.
If it is necessary to change the nominal voltage:
1. Reset the FLEXmax 100 to factory default settings as described in the next section.
2. Remove all sources of power (PV and battery) from the FLEXmax 100 and then reconnect
battery power.
The controller will sense the battery voltage and use this reading to determine the new nominal
system voltage. This will not occur until the power is turned off and then on again.