Theory Of Operation - Vector MAXX SST 1000 VEC049 Owner's Manual

The inverter can be operated in any position, however, if it is to be
mounted on a wall, mount it horizontally so that indicators, switches,
outlets and terminal blocks located on the front panel are visible and
accessible. If inverter is to be installed in a moving vehicle, Vector strongly
recommends that the inverter be shock-mounted either on the floor (in a
clear, safe area) or on a secure flat surface. Look for a convenient place
to mount inverter and the fuse holder. Take the length of cable and do a
trial routing of the cable. Don't do any cutting at this time. Take a look at
FIGURE 7 . Measure the cable path and ensure that either the positive cable
run to the battery or negative cable run to the battery does not exceed 4
feet. Using #4 AWG reposition the inverter and fuse holder if necessary.
Remember and observe the other environmental requirements described
earlier.
After you have selected an appropriate location for the inverter and fuse
block, proceed with the actual installation of the inverter.
Contact Vector Manufacturing for any further installation information or
™
questions. You can purchase fuses, fuse holders, #4 AWG cable or cable
battery connectors from your local electrical supplier or call Vector
Technical Support at (954) 584-4446 Ext. 119 for advice.
17
Common unattended applications for the UPS (floating battery) configura-
tions are for powering: sump pumps, safety lighting, communications
equipment, burglar alarm systems and computer systems.

3.0 THEORY OF OPERATION

MAXX SST™ inverters change 12 VDC into 110 VAC (110 VAC RMS), elec-
trical power. This is accomplished in two steps. See FIGURE 4.
The first stage raises the 12 VDC input to 145 VDC. The advanced
design of the DC-to-DC first stage uses modern high-frequency conversion
techniques that replace bulky and heavy transformers found in older, less
technologically-advanced inverters. The output stage changes the 145-VDC
to 110 VAC. This solid-state circuitry ensures excellent overload protection
and the ability to operate reactive loads such as those found in inductive
motors and most fluorescent lamps. The inverter's output stage uses multiple
banks of metal-oxide semiconductor field-effect transistors (MOSFETS). This
stage functions as a high-power bipolar switch, alternately applying oppo-
site polarity to the AC outlet HOT and NEUTRAL terminals.
100 AMP
DC to DC
TERMINAL
CONVERTER
BLOCK
#4 AWG
INTERNAL WARNINGS &
WIRE
PROTECTION CIRCUITS
200
AMP
VOLT, AMP METERS*
FUSE
OVER TEMP &
VOLT INDICATORS
ON/OFF
#4 AWG #4 AWG
SWITCH
WIRE WIRE
+
–
12 VOLT DC
INPUT FROM
NOTE: Cables, Fuse and
BATTERY
Battery Are Supplied By User
Figure 4 Simplified Diagram
• Some Models only include volt, Amp and over temp indicators.
+
145 VDO
–
MOSFET
BIPOLAR
SWITCH
BANKS
Neutral Hot
VEC049
THREE
OUTLETS
Ground
6