Power Star W7 Pure Sine Wave Inverter/Charger User’s Manual www.sigineer.com
6
by a large input capacitor and switched “On” and “Off” by the Metal Oxide Silicon Field Effect Transistors
(MOSFET) at a rate of 50 Hz or 60Hz, and directed into the transformer which steps the voltage up to 230 or
120 volts. The unit has a 16bit, 4.9MHZ microprocessor to control the output voltage and frequency as the
DC input voltage and/or output load varies.
Because of high efficiency MOSFETs and the heavy transformers, it outputs PURE SINE WAVE AC.
The peak invert efficiency of PSW7 Series is 90%.
Overload Capacity
The Power Star inverter charger has different
overload capacities, making it ideal to handle
demanding loads.
1 For 110%<Load<125% (±10%), no audible alarm
in 14 minutes, beeps 0.5s every 1s in the 15th minute,
and Fault (Turn off) after the 15th minute.
2 For 125%< Load<150% (±10%), beeps 0.5s every 1s and Fault (Turn off) after the 1 minute.
3 For 300%≧Load>150% (±10%), beeps 0.5s every 1s and Fault (Turn off) after 20s.
Caution:
After the inverter is switched on, it takes 3-5 seconds for it to self diagnose and get ready to deliver full
power. Hence, always switch on the load(s) after a few seconds of switching on the inverter. Avoid
switching on the inverter with the load already switched on. This may prematurely trigger the overload
protection. When a load is switched on, it may require initial higher power surge to start. Hence, if multiple
loads are being powered, they should be switched on one by one so that the inverter is not overloaded by the
higher starting surge if all the loads are switched on at once.
2.5.2 AC Charger
The PSW7 Series pure sine wave inverter/charger is equipped with an active PFC (Power Factor Corrected)
multistage battery charger. The PFC feature is used to control the amount of power used to charge the
batteries in order to obtain a power factor as close as possible to 1.
Unlike other inverters whose max charging current decreases according to the input AC voltage, PSW7
Series pure sine wave inverter/charger is able to output max charge current as long as input AC voltage is in
the range of 164-243VAC(95-127VAC for 120V model), and AC freq is in the range of 48-54Hz(58-64Hz
for 60Hz model).
The PSW7 Series pure sine wave inverter/charger has a very rapid charge current available, and the max
charge current can be adjusted from 0%-100% via a liner switch on the DC side of the inverter. This will be
helpful if this powerful charger apply charging on a small capacity battery bank.
Choosing “0” in the battery type selector will disable charging function.
There are three main charging stages:
Bulk Charging: This is the initial stage of charging. While Bulk Charging, the charger supplies the battery
with controlled constant current. The charger will remain in Bulk charge until the Absorption charge voltage
(determined by the Battery Type selection) is achieved.
Software timer will measure the time from charger start until the battery charger reaches 0.3V below the
boost voltage, then take this time as T0 and T0×10 = T1.