Tadiran Telecom Coral IPx 800 Series Installation Procedure And Hardware Reference Manual page 321

-48VDC Output Power
The PS19 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 approximately 1.5V to 2.0V
lower than the input voltage to the PS19 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 PS19 DC (including
message and ring generator currents), 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
–48VDC output) is within specification. If any of the voltage outputs drop below
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 of the PS19 DC remains illuminated at the same time as the red alarm
indicator.
If the Input voltage drops below 36.5±1VDC, the unit shuts down and returns to power
only when the voltage increases above 38.5±1VDC again. Additionally, if the voltage
is greater than 62±1VDC, then the unit shuts down until the input voltage drops below
58±1VDC.
7-7
Power Supplies