SamplexPower Evolution Series Owner's Manual page 9

SECTIOn 1 |
lamps, Quartz/Halogen lamps and Quartz / Halogen Infrared heaters. These require higher start-
ing surge power due to lower resistance value when the heating elements are cold).
reactive Load: A device or appliance that consists of a combination of resistive, inductive and
capacitive elements (like motor driven tools, refrigeration compressors, microwaves, computers,
audio/ video etc.). The Power factor (Pf) of this type of load is < 1 e.g. AC Motors (Pf = 0.4 to
0.8), AC to DC Switch Mode Power Supplies (Pf = 0.5 to 0.6), Transformers (Pf = 0.8) etc. These
devices require Apparent Power (VA) from the inverter to operate. The Apparent Power is a vecto-
rial sum of Active Power (Watts) and reactive Power (VAr). The inverter has to be sized based on
the higher Apparent Power (VA) and also based on the Starting Surge Power.
1.3 generAL inForMAtion - inVerter reLAteD
General information related to operation and sizing of inverters is given in succeeding sub-sections.
1.3.1 AC Voltage waveforms
360
320
280
240
200
160
120
80
40
0
40
Pure Sine Wave
80
crosses zero V
120
instantaneously
160
200
240
280
320
360
TIME
The 230VAC output waveform of the Evolution
waveform of Utility / Grid power. Please see Sine Waveform represented in the fig. 1.1 that also
shows equivalent Modified Waveform for comparison.
In a Sine Wave, the voltage rises and falls smoothly with a smoothly changing phase angle and
also changes its polarity instantly when it crosses 0 Volts. In a Modified Sine Wave, the voltage
rises and falls abruptly, the phase angle also changes abruptly and it sits at 0V for some time
before changing its polarity. Thus, any device that uses a control circuitry that senses the phase
(for voltage / speed control) or instantaneous zero voltage crossing (for timing control) will not
work properly from a voltage that has a Modified Sine Waveform.
Also, as the Modified Sine Wave is a form of Square Wave, it is comprised of multiple Sine Waves
of odd harmonics (multiples) of the fundamental frequency of the Modified Sine Wave. for exam-
ple, a 50 Hz Modified Sine Wave will consist of Sine Waves with odd harmonic frequencies of 3rd
Safety Instructions & general Information
V = 325.22V
peak
V
peak
V
20 ms
Fig 1.1 Pure and Modified Sine waveforms for 230VAC, 50 hz
= 250 to 320V
= 230 VAC
RMS
Modi ed Sine
Wave sits at
ZERO for some
time and then
rises or falls
series inverters is a Pure Sine Wave like the
TM
Sine Wave
V = 230VAC
•
RMS
V = 325.22V
•
peak
Modi ed Sine Wave
V = 230V
•
RMS
V = 250 to 320V
•
peak
SAMLEX AMErICA INC. | 9