Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) - Classic Control - Manual (Page 365)

Component Definition and Maintenance 6-75
7000 “B” Frame 7000-UM150I-EN-P – June 2013
DC/DC Power Supply Description
The DC/DC power supply is used as a source of regulated DC
voltage for various logic control boards and circuits. The input
to this power supply is from a regulated 56Vdc source.
+24V - PRINTER,I/O
DC/DC
Power Supply
C
hold-up
DC/DC
WARN
SPGDB TEST
POWER ON
+5V - DCB LOGIC
+/-15V - DCB LOGIC
+/-24V - LEM
+12V - REM I/O
+15V - TACH
DC/DC
FAIL
+15V - SPGDB TEST
56 Vdc
-
+
Figure 6.56 – DC/DC converter power supply
The capacitor at the input terminals is for power dip ride-through
purposes. Upon loss of the 56V input, the capacitors (C hold-up)
will maintain the voltage level.
Due to the critical nature of the DCB Logic power source, the
DC/DC power supply has been designed to provide redundancy for
these voltages. Each of the DCB Logic outputs is supplied internally
with two separate sources of power. In the event of one failing, the
other power supply will be automatically switched in to provide the
output power.
DC FAIL – Each output to be internally monitored with a single
output fail. This output goes from low to high when any of the non-
redundant outputs fail or both of the redundant outputs of one
particular voltage fails (output voltage is < 95%).
DC WARNING – Each redundant output to be internally monitored
with a single output warning. This output goes from low to high
before loss of output regulation of any one of the redundant outputs
(output voltage is <95%).
SPGDB TEST POWER ON – The +15V output on COM4 will
have its load current monitored. This open collector output goes
from low to high when the load current exceeds 20 mA. The
purpose of this signal is to inform the user that the test harness for
the SCRs is still attached to the DC/DC converter.