
12 | SAMLEX AMErICA INC.
SAMLEX AMErICA INC. | 13
The inverter should, therefore, be sized adequately to withstand the high inrush current and the
high Crest factor of the current drawn by the SMPS. Normally, inverters have short duration Surge
Power rating of 2 times their Maximum Continuous Power rating.
hence, it is recommended
that for purposes of sizing the inverter, to accommodate Crest Factor of 3, the Maxi-
mum Continuous Power rating of the inverter should be > 2 times the Maximum Con-
tinuous rated Power of the SMPS. For example, an SMPS rated at 100 watts should be
powered from an inverter that has Maximum Continuous Power rating of > 200 watts.
Input voltage
Peak Inrush Current
Inrush current
Rated Steady State
Input RMS Current
NOTE:
Voltage and
Current scales
are different
Fig 1.2 inrush current in an SMPS
TIME
Peak Current
RMS Current
Non-linear
Input Current
Input Sine
Wave Voltage
CREST FACTOR = PEAK CURRENT = 3
RMS CURRENT
NOTE: Voltage and
Current scales
are different
Vola
tge −
V
Cur
ren
t −
Cur
ren
t +
Fig 1.3 high Crest Factor of current drawn by SMPS
1.4 generAL inForMAtion - LeAD ACiD bAtterieS
inFo
for complete background information on Lead Acid batteries and Charging Process, visit www.
samlexamerica.com>Support>White Papers>Whitepaper - batteries, Chargers and Alternators.
SECTIOn 1 |
Safety Instructions & general Information
Содержание Evolution Series
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