Principle Of Operation - Vector MAXX SST VEC049D User's Manual & Warranty Information

PRINCIPLE OF OPERATION

The MAXX SST
™
other 12 volt DC power source to standard 120 volt AC (alternating current)
household power.
It converts power in two stages (see the diagram below). In the first stage, the inverter
raises the 12 volt DC input to 145 volts DC. This MAXX SST
frequency conversion techniques that replace bulky and heavy transformers found in
older inverters. In the second (output) stage, the inverter converts the 145 volt DC to
110/120 volt AC using multiple banks of metal-oxide semiconductor field-effect
transistors (MOSFETs). The unit's solid-state circuitry ensures excellent overload
protection and the ability to operate reactive loads such as those found in inductive
motors. In this stage, the inverter functions as a high-power bipolar switch, alternately
applying opposite polarity to the AC outlet HOT and NEUTRAL terminals.
See Specifications on
page 16 for wire
gauges and fuse
amperages.
Notes:
Simplified diagram.
Cables, fuse and battery are not included and must be supplied by user.
The Power Inverter Output Waveform
The AC output waveform of the Power Inverter is known as "modified sine wave." It
is a waveform 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 Power Inverter has an RMS (root mean
square) voltage of 115 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
179, Fluke 79 III series, Beckman 4410 or Triplett 4200.
Modified Sine Wave and Sine Wave Comparison
inverter converts 12 volt DC (direct current) from a vehicle battery or
TERMINAL
BLOCK
AWG
WIRE
ANL
FUSE
(external)
AWG
WIRE
+ –
12 VOLT DC
INPUT FROM
BATTERY
SINE WAVE
DC TO DC
CONVERTER
INTERNAL WARNINGS &
PROTECTION CIRCUITS
VOLT, AMP METERS*
OVER TEMP &
VOLT INDICATORS
AWG
ON/OFF
WIRE
SWITCH
4
inverter uses high-
™
+
–
NEUTRAL
(2, 3 OR 4)
OUTLETS
MODIFIED
SINE WAVE
145 VDC
MOSFET
BIPOLAR
SWITCH
BANKS
HOT
GROUND
FAULT
SENSE