Battery Charging - Magnum Energy MagnaSine Hybrid MSH3012RV Owner's Manual

3.2.1

Battery Charging

The MSH3012RV is equipped with a PFC (Power Factor Corrected) and PI (Proportional-Integral)
multi-stage battery charger. The PFC feature controls the amount of power used to charge the
batteries to obtain a power factor as close as possible to 1 (or unity). This causes the battery charger
to look like a resistor to the line (forces the charge current wave shape to mirror the voltage wave
shape). The PI feature allows the charger voltage and current to change independently. These
two features maximize the real power available from the AC power source (i.e., shorepower or
generator), which translates into less power wasted and greater charging capabilities.
When an AC input source is fi rst connected, the inverter begins monitoring for acceptable AC
voltage and frequency. Once the AC source is accepted and after the transfer relay has closed,
the inverter's battery voltage is monitored to determine the charging stage. If the battery voltage
is ≤12.8 VDC, the charger begins Bulk charging. If the DC voltage is >12.8 VDC, the charger will
skip the Bulk and Absorb charge stages and go directly to the Float charge stage. However, if the
incoming AC power is lost and returns within 2 minutes, the charge mode returns to the charge
stage it was in prior to losing AC input—regardless of the battery voltage.
The MSH3012RV's multi-stage charger can use up to fi ve different charging stages to help keep
the batteries healthy. The fi ve stages include an automatic 4-stage charging process (see Figure
3-4): Bulk, Absorb, Float, and Full Charge; and a manual Equalization (EQ) charge stage. The
automatic 4-stage charge process provides complete recharging and monitoring of the batteries
without damage due to overcharging. The EQ stage (requires a remote control display to enable)
is used to stir up stratifi ed electrolyte and to reverse any battery plate sulfation that may have
occurred—if recommended by your battery's manufacturer.
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
blinks 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 blinks 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 (12.7 VDC or less), the charger automatically initiates another four hours in fl oat charge.
Info: While charging, the unit may automatically reduce the charge current to the
batteries. This charger back-off feature can be caused by: 1) The internal temperature
is too hot—the charger automatically reduces the charge rate to maintain temperature;
or 2) The AC input voltage falls below 90 VAC—the charger will stop charging to help
stabilize the incoming AC voltage.
Info: If the battery voltage falls to the re-bulk voltage (12.1 VDC) or lower, the unit
will begin another bulk charge.
* These settings in the MSH3012RV are changeable and 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 need to be changed for your particular system, a
remote control may be purchased to adjust these settings.
© 2020 Sensata Technologies
Operation
Page 34