Owner`s manual
3. HOW YOUR INVERTER WORKS
The inverter converts low voltage DC (direct current) from a battery or other power source
to standard 120 volt AC (alternating current) household power.
3.1 PRINCIPLE OF OPERATION
The inverter converts power in two stages. The first stage is a DC-to-DC conversion
process that raises the low voltage DC at the inverter input to 145 volts DC. The second
stage is the actual inverter stage that converts the high voltage DC into 120 volts, 60 Hz
AC.
The DC-to-DC converter stage uses modern high frequency power conversion techniques
that have replaced the bulky transformers found in less technologically-advanced models.
The inverter stage uses advanced power MOSFET transistors in a full bridge configuration.
This ensures excellent overload capability and the ability to operate reactive loads like
small induction motors.
FIGURE 3 PRINCIPLE OF OPERATION
3.2 THE
VECTOR POWER INVERTER OUTPUT WAVEFORM
The AC output wave form of the Vector Power Inverter is known as “modified sine wave”.
It is a wave form that has characteristics similar to the sine wave shape of utility power. This
type of waveform is suitable for most AC loads, including linear and switching power
supplies used in electronic equipment, transformers, and motors.
The modified sine wave produced by the Vector Power Inverter has an RMS (root mean
square) voltage of 120 volts, which is the same as standard household power. Most AC
voltmeters (both digital and analog) are sensitive to the average value of the waveform
rather than the RMS value. They are calibrated for RMS voltage under the assumption that
the waveform measured will be a pure sine wave. These meters will not read the RMS
voltage of a modified sine wave correctly. They will read about 20 to 30 volts low when
measuring the output of the inverter. For accurate measurement of the output voltage of
this unit, use a true RMS reading voltmeter such as a Fluke 87, Fluke 8060A, Fluke 77/99
series, Beckman 4410, or Triplett 4200.
FIGURE 4 Modified Sine Wave and Sine Wave Comparison
5
12VDC to
145VDC
CONVERSION
145VDC to
120VAC
CONVERSION
Internal
Fuses
Two AC
Outlets
12VDC
Input
120VAC, 60Hz
to AC appliances
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