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INVERTER RELATED
Preventing paralleling of the AC output
The AC output of this inverter cannot be synchronised with another AC source and
hence, it is not suitable for paralleling. The AC output of the inverter should never be
connected directly to an electrical breaker panel / load center which is also fed from
the utility power / generator. Such a connection may result in parallel operation of the
different power sources and AC power from the utility / generator will be fed back
into the inverter which will instantly damage the output section of the inverter and
may also pose a fire and safety hazard. If an electrical breaker panel / load center is
fed from an inverter and this panel is also required to be powered from additional
alternate AC sources, the AC power from all the AC sources like the utility / generator
/ inverter should first be fed to a manual selector switch and the output of the selector
switch should be connected to the electrical breaker panel / load center.
To prevent possibility of paralleling and severe damage to the inverter, never use a
simple jumper cable with a male plug on both ends to connect the AC output of the
inverter to a handy wall receptacle in the home / RV.
Connecting to multi-wire branch circuits
Do not directly connect the hot side of the inverter to the two hot legs of the 120 /
240 VAC electrical breaker panel / load centre where multi-wire ( common neutral )
branch circuit wiring method is used for distribution of AC power. This may lead to
overloading / overheating of the neutral conductor and is a risk of fire.
A split phase transformer ( isolated or auto-transformer ) of suitable wattage rating
( 25 % more than the wattage rating of the inverter ) with primary of 120 VAC and
secondary of 120 / 240 VAC ( Two 120 VAC split phases 180 degrees apart) should be
used. The hot and neutral of the 120 VAC output of the inverter should be fed to
the primary of this transformer and the 2 hot outputs ( 120 VAC split phases ) and the
neutral from the secondary of this transformer should be connected to the electrical
breaker panel / load centre.
Preventing input over voltage
It is to be ensured that the input voltage of the inverter does not exceed 16.5 VDC
(PST-30S-12A) or 33 VDC (PST-30S-24A) to prevent permanent damage to the inverter.
Please observe the following precautions:
•
Ensure that the maximum charging voltage of the battery charger / alternator /
solar charge controller is below 16.5 VDC (PST-30S-12A) or 33 VDC (PST-30S-24A)
•
Do not use unregulated solar panels to charge a battery. Under cold ambient
temperatures, the output of the solar panel may exceed 18 VDC for 12V battery
system of 36VDC for 24V battery system. Always use a charge controller between
the solar panel and the battery.
•
Do not connect the inverter to a battery that has a voltage higher than the rated
battery input voltage of the inverter.
Preventing reverse polarity on the input side
When making battery connection on the input side, make sure that the polarity of
battery connection is correct (Ensure that the centre contact of the cigarette lighter
receptacle is connected to the positive of the battery. The centre pin (tip) of the
cigarette lighter plug attached to the inverter is positive). If the input is connected in
reverse polarity, DC fuse inside the inverter will blow and may also cause permanent
damage to the inverter.
