10 | SAMLEX AMERICA INC.
SAMLEX AMERICA INC. | 11
Load:
Electrical appliance or device to which an electrical voltage is fed.
Linear Load:
A load that draws sinusoidal current when a sinusoidal voltage is fed to it. Examples
are, incandescent lamp, heater, electric motor, etc.
Non-Linear Load:
A load that does not draw a sinusoidal current when a sinusoidal voltage is
fed to it. For example, non-power factor corrected Switched Mode Power Supplies (SMPS) used
in computers, audio video equipment, battery chargers, etc.
Resistive Load:
A device or appliance that consists of pure resistance (like filament lamps, cook
tops, toaster, coffee maker etc.) and draws only Active Power (Watts) from the inverter. The
inverter can be sized based on the Active Power rating (Watts) of the Resistive Load without
creating overload (except for resistive loads with Tungsten based heating element like filament
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
TIME
180
160
140
120
100
80
60
40
20
0
20
40
60
80
100
120
140
160
180
Modified Sine
Wave sits at
ZERO for some
time and then
rises or falls
Pure Sine Wave
crosses zero V
instantaneously
Modified Sine Wave
•
V
RMS
= 120V
•
V
peak
= 140 to 160V
Sine Wave
•
V
RMS
= 120VAC
•
V
peak
= 169.68V
16.66 ms
VOL
TS
−
VOL
TS +
V
peak
= 169.68V
V
peak
= 140 to 160V
V
RMS
= 120 VAC
Fig 1.1 Pure and Modified Sine Waveforms for 120V, 60 Hz
SECTION 1 |
Safety Instructions & General Information
Содержание Evolution EVO-1212F
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