Samlexpower PST-1000-12 Owner's manual - Section 4 |
12 | SAMLEX AMERICA INC.
SECTION 4 |
Powering Direct / Embedded Switch
Mode Power Supplies (SMPS)
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inrush current drawn by the power supply as the input capacitors are charged (The ca-
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current at turn-on is several to tens of times larger than the rated RMS input current
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waveforms is given in Fig. 4.1. It will be seen that the initial input current pulse just after
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in Fig 4.2 above. The steady state input current of SMPS is a train of non-linear pulses
instead of a sinusoidal wave. These pulses are two to four milliseconds duration each
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the input to the power supply. The cold resistance limits the input current as the input
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current event.
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that for purposes of sizing the inverter, the continuous power of the inverter should be
> 3 times the continuous rated power of the SMPS. For example, an SMPS rated at
100 Watts should be powered from an inverter that has continuous power of
> 300 Watts.