Whistler PP750 Owner's Manual page 10

PP750 Manual 3/6/02 2:25 PM Page 19
OPERATING PRINCIPLES
For You Technical Types.
1. Basic Operating Principles:
Whistler GO AC inverters work in two stages. During the first
stage, the DC to DC converter increases the DC input voltage
f rom the power source (e.g. a 12 volt battery) to 145 volts DC.
In the second stage, the high voltage DC is converted to 110
volts (60 Hz AC) using advanced power MOSFET transistors
in a full bridge configuration. The result is excellent overload
capability and the capacity to operate difficult reactive loads.
The output waveform resulting from these conversions is a
"quasi-sine wave" or a "modified sine wave" as shown on the
following page.
This stepped waveform is similar to the power generated by
utilities and has a broad range of applications.
The modified sine wave produced by
your Whistler GO AC Inverter
The modified sine wave produced by your Whistler invert e r
has a root mean square (RMS) voltage of 110 volts. The
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OPERATING PRINCIPLES
majority of AC voltmeters are calibrated for RMS voltage
and assume that the measured waveform will be a pure sine
w a v e .
C o n s e q u e n t l y, these meters will not read the RMS modified
sine wave voltage correctly and, when measuring your
Whistler i n v e rter output, the meters will read about 20 to 30
volts too low. To accurately measure the output voltage of
your invert e r, use a true RMS reading voltmeter such as a
Fluke 87, Fluke 8060A, Beckman 4410, Triplett 4200 or any
multimeter identified as "True RMS."
For more information on inverters see our Inverter FA Q
page at www. w h i s t l e rg ro u p . c o m / f a q - i n v e rt e r s . a s p
A true sine wave typical of home AC outlet.
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