Whistler PP200 Owner's Manual page 10

200/400 Watt Series 3/6/02 3:05 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 from the power source (e.g. a 12 volt battery) to 145
volts DC. In the second stage, the high voltage DC is con-
v e rted to 110 volts (60 Hz AC) using advanced power MOS-
FET transistors in a full bridge configuration. The result is
excellent overload capability and the capacity to operate dif-
ficult reactive loads. The output waveform resulting fro m
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 inverter output, the meters will read about 20 to
30 volts too low. To accurately measure the output volt-
age 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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