Tadiran Telecom Coral IPx 500, Руководство по установке

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Power Supply
7-5
PS5
00 DC Power Supply
Un
it
7
0
Figure 7-3 presents a block diagram of the PS500 DC power supply.
Power Input Section
The DC input includes a passive filter, inrush current, and an ON/OFF power switch.
The DC input is protected against reverse polarity.
DC Output Power
The DC to DC converters convert the –48VDC power to the following outputs:
„
+5VDC
„
–5VDC
„
+12VDC
-48VDC Output Power
The PS500 DC also filters and limits the -48VDC input to feed the peripheral card
slots.
Ripple and Noise
Filtering circuitry minimizes ripple and noise on the –48VDC feed to the peripheral
cards. The filtering circuitry produces an output voltage that is approximately 0.5V to
1.0V lower than the input voltage -VIN to the PS500 DC.
Monitoring Circuitry
All outputs, with the exception of the –48VDC output, are regulated. Voltage and
current level monitoring circuitry check each output of the PS500 DC, and produce an
alarm signal to the Coral system main processor in the event of malfunction.
Monitoring circuitry verifies that each voltage output (with the exception of the
–48 VDC output) is within specification. If any voltage deviates from specification,
the monitoring circuitry produces an alarm signal to the Coral system processor,
causing the red Alarm indicator to illuminate. Note that the green Power indicator
remains illuminated at the same time as the red alarm indicator.
If the voltage input is less than –38
±0.5
VDC or greater than –62
±0.5
VDC, then the
power supply shuts down. The power supply will turn on when the voltage is less than
–58
±0.5
VDC or greater than –45
±0.5
VDC.
2 Circuit Description