Vector MAXX SST VEC049C User Manual
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2.0 INVERTER APPLICATIONS
Aside from issues of supplying power to higher wattage appliances, inverters
must be supplied with a constant source of high current 12VDC from a bank of
batteries. At full watt load, the DC input requirements are up to 15 amps at
12VDC.
Read and comply with the following applications, and your inverter will give
you years of reliable service.
2.1 UNINTERRUPTIBLE POWER SUPPLY (UPS)
Inverters can be operated as uninterruptible power supplies that continuously
provide AC even if outside AC is interrupted. This function continuously
operates the inverter from a battery bank, simultaneously replacing the charge
to the battery bank with an AC-powered 12 volt battery charger. Charging can
also be by means of a solar charger system. (
See FIGURE 3). The charger must
be selected to operate continuously in order to fully replace the charge on the
battery as the inverter operates. In this configuration, the battery "floats" on the
DC from the charger, not really supplying power or being charged. When out-
side AC fails, the inverter continues to power the appliances for the life of the
useful charge of the battery bank. When outside AC is restored, the batteries
are charged as the inverter continues to operate. Battery charging must be
sized to replace the average current supplied by the inverter plus a little more
current. Another requirement is that the battery charging rate cannot exceed
10% of the Ampere Hour (AH) rating of the battery bank, otherwise the life of
the batteries can be dramatically reduced through overcharging. Most modern
battery chargers automatically adjust the charging rate based on the state of
charge on the batteries they are charging. For this type of operation, use deep-
cycle batteries and avoid charging at too fast a rate.
Common unattended applications for the UPS (floating battery) include power-
ing: sump pumps, safety lighting, communications equipment, burglar alarm
systems and computer systems.
Figure 3 – Uninterruptible Power Supply
WARNING:
Never connect the inverter’s AC output to an
AC distribution system.
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