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BACK OF UNIT (ALL UNITS)
7. Positive (+) DC Power Connection
8. High-Speed Cooling Fans
9. Negative (–) DC Power Connection
10. Grounding Post
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HOW THESE INVERTERS WORK
Your inverter converts low voltage DC (direct current) electricity from a battery to 115 volt AC (alternating current)
household power in two stages. The first stage is a DC-to-DC conversion process that raises the low voltage DC
at the inverter input to 145 volts DC. The second stage converts the high voltage DC into 115 volts, 60 Hz AC.
Power Inverter Output Waveform
The AC output waveform of your inverter is known as a modified sine wave. It is a stepped waveform that has
characteristics similar to the sine wave shape of utility power. This type of waveform is suitable for most AC loads,
including linear and switching power supplies used in electronic equipment, transformers and small motors.
The modified sine wave produced by this inverter has an RMS (root mean square) voltage of 115 volts. Most AC
voltmeters (both digital and analog) are sensitive to the average value of the waveform rather than the RMS value.
They are calibrated for RMS voltage under the assumption that the waveform measured will be a pure sine wave.
These meters will not correctly read the RMS voltage of a modified sine wave. Non-TRUE RMS meters will read
about 20 to 30 volts low when measuring the output of this inverter. For accurate measurement of the output voltage
of this unit, use a TRUE RMS reading voltmeter such as a Fluke 87, Fluke 8080A, Beckman 4410 or Triplett 4200.
115 VOLT AC OUTPUT
Q: Why don't I measure rated voltages when using a
multimeter on my power inverter?
A. Most multimeters are designed to give correct RMS readings
when applied to sine waves, but not when they are applied to
other waveforms. They will read from 2% to 20% low in voltage.
Look for a voltmeter that brags about "True RMS" readings, and
that will read correctly no matter what the wave shape is
