Installation Manual

© 2015 Sensata Technologies
Page 33
Operation
The Charge mode provides up to four separate charging stages: Bulk Charging, Absorb Charging,
Float Charging, and Full Charge.
Bulk Charging: This is the initial stage of charging. While bulk charging, the charger supplies the
battery with controlled constant current. The charger will remain in bulk charge until the absorption
charge voltage (determined by the Battery Type selection*) is achieved. The inverter’s green LED
stays on (solid) to indicate bulk charging.
Absorb Charging: This is the second charging stage and begins after the absorb voltage has
been reached. Absorb charging provides the batteries with a constant voltage and reduces the
DC charging current in order to maintain the Absorb Voltage setting. The inverter’s green LED
fl ashes once every second (fast fl ash) to indicate absorption charging for 2 hours (determined by
the Battery AmpHrs selection*), then switches to fl oat charging.
Float Charging: The third charging stage occurs at the end of the absorb charging time. While
fl oat charging, the charge voltage is reduced to the fl oat charge voltage (determined by the
Battery Type selection*). In this stage, the batteries are kept fully charged and ready if needed by
the inverter. The inverter’s green LED fl ashes once every 8 seconds (slow fl ash) to indicate fl oat
charging. The Float Charging stage reduces battery gassing, minimizes watering requirements (for
fl ooded batteries), and ensures the batteries are maintained at optimum capacity.
Full Charge (Battery Saver™ mode): The fourth stage occurs after four hours in the Float
Charging stage. The Full Charge stage is designed to keep batteries fully charged over long periods,
and to prevent excessive loss of water in fl ooded batteries or drying out of GEL/AGM batteries.
In this stage, the charger is turned off and begins monitoring the battery voltage. If the battery
voltage drops low (25.4 VDC or less on 24-volt models, or 50.8 VDC or less on 48-volt models),
the charger automatically initiates another four hours of fl oat charging.
Info: If the battery voltage falls to the rebulk voltage (24.2V on 24-volt models or
48.4V on 48-volt models) or lower, the unit will begin another bulk charge.
* These settings in the MS-PAE Series leave the factory with default values (see Table 3-2, Inverter/
Charger Default Values). These default values are adequate for most installations, however if
you determine that some of the values are not adequate they can be changed for your particular
system. The ME-RC50 or ME-ARC remote control may be purchased to adjust these settings.
Figure 3-3, Automatic 4-Stage Charging Graph
Constant
Current
Reduced
Current
Reduced
Voltage
Absorb
volts
Max
Charge
Rate
Increased
Voltage
Constant
Voltage
Monitored
Voltage
No Current
Monitored
Current
Bulk
Charging
Absorb
Charging
Float
Charging
Full
Charge
Goes to Full
Charge after
4 hours in
Float Charge
Absorb
Time
Float
volts
Time
DC
Voltage
DC
Current