Power Source; How Power Converters Work; Led Indicator And Shutdown Protection - Schumacher Electric XI41B Owner's Manual

Your average automobile or marine battery at full charge will provide an ample
power supply to the converter for approximately 3 hours when the engine is
off. The actual length of time the converter will function depends on the age
and condition of the battery and the power demand being placed by the device
being operated with the converter.
If you decide to use the converter while the engine is off, we recommend
you turn OFF the device plugged into the converter and disconnect the
converter's plug from the 12 volt accessory outlet before starting the engine.
To maintain battery power, start the engine every 2 to 3 hours and let it run for
approximately 10 minutes to recharge the battery.
Although it is not necessary to disconnect the converter when turning over
the engine, it may briefly cease to operate as the battery voltage decreases.
While the converter draws very low amperage when not in use, it should be
unplugged to avoid battery drain.
There are two stages involved in transforming 12 volt DC (battery) power into
120 volt AC (household voltage):
STAGE 1: The power converter uses a DC to DC transformer to increase the
12-volt DC input voltage from the power source to 145 volt DC.
STAGE 2: The converter then converts the 145 volt DC into 120 volts AC
(household voltage) using advanced MOSFET transistors in a full bridge
configuration. A "modified sine wave" waveform is generated by this conversion.

LED INDICATOR AND SHUTDOWN PROTECTION

The LED glows GREEN when the switch is on, and under the following conditions:
1. When the power input from the vehicle's battery drops to approximately 10
volts, low battery shutdown occurs and the converter shuts off. The Green
and Red LEDs are on, with a buzzer.
Recharge or replace the battery.
2. When the power input from the vehicle's battery exceeds 15 volts, high voltage
overload protection occurs. The Green LED is on, and the buzzer will sound.
Reduce the voltage range to between 12 volts and 14 volts.
3. The continuous load demand from the equipment or device being operated
exceeds the continuous load rating of the converter being used. The output
pulses ON and OFF; the Green LED is on.
Use a higher capacity converter or lower rated device.

POWER SOURCE

HOW POWER CONVERTERS WORK

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