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DESCRIPTION AND OPERATION
STATUS SIGNALS
I-E96-508C
2 - 5
All output voltages are preset at the factory. In an N+1 redun-
dant environment, proper operation of each module output is
based on this preset voltage. If a bus requires more current,
the module automatically compensates.
NOTE: The factory preset voltages are not field-adjustable.
The IEPDF01 and IEPDF02 DC Field Power Modules are func-
tionally the same as the IEPDS01 or IEPDS02 modules except
that they provide only 24 VDC. The DC field power module pro-
vides power to field termination devices when separate termi-
nation cabinets are used, or when it is desirable to separate the
I/O power supplies from the module power supplies.
STATUS SIGNALS
The block diagram in Figure
shows the flow of status sig-
nals through the system. The following text explains status sig-
nal flow.
Power System Status
The bus monitor module logically ANDs all status lines (DC
line, bus voltages, external power inputs, external user status
inputs and power module status). Internal bus monitor
Figure 2-3. Block Diagram, Power Distribution to the PDS
BMM
POWER ENTRY PANEL
MODULE MOUNTING UNIT
OR
POWER MOUNTING UNIT
POWER SUPPLY MODULE
DC
CONV
DC
CONV
DC
CONV
±15 VDC
ALARMS
TP25131B
+24 VDC
+5 VDC
DC OUT
DC IN
SOFT START AND
HOLD UP CIRCUITRY
TO PROCESS
CONTROL
MODULES
STATUS OUT
PDS
FAN ASSEMBLY
DTM