Reference Manual

Unit Description, PSU 1200 W
Boost Converter
Draws a sinusoidal input current in phase with the input voltage,
enabling the power supply to have a high power factor and low
distribution on input current. The output from the boost converter is
400 V DC.
DC/DC Converter
A phase-shifted, soft-switched, full-bridge converter that converts the
incoming 400 V DC to 24 V DC output voltage.
The output provides constant power regulation, rather than the more
common current limited, and delivers 1200 W over the whole output
range from 22 to 29 V DC.
Control and Supervision Circuits
The control and supervision circuits support:
• load sharing between parallel units
•
remote on/off
•
alarms
The output voltage can be adjusted between 22 to 29 V DC. The
control and supervision is achieved through an optical signal interface
connector on the front of the PSU.
Output Filter
The output voltage is filtered to prevent unwanted signals from being
radiated from the PSU.
12.1.2 Functions
The PSU AC has the following functions:
•
Communication
• Handling alarms
• Voltage adjustment
•
Power limitation
Communication
The PSU communicates with its superior unit (DXU) through an optical
interface. The PSU is controlled and supervised through this interface.
In the event of communication failure, the PSU continues working with
default values.
Alarms
The following alarms are detected in the rectifier and are then
forwarded to the DXU and an indicator is illuminated on the PSU front:
• Rectifier failure
144 (421)
EN/LZT 720 0008 R1A
2001-06-26
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