Operating instructions

Operation SW 5250A•SW 3500A•SW 1750A
3-30 Operation Manual
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F4:OT Monitors power stage heat sink temperatures.
Action: Opens relays, displays error message for 30 seconds,
then shuts off SW system.
F2:OV Indicates that the internal DC bus has pumped up to an
unacceptable level (due to sinking power rather than sourcing,
i.e., attempting to discharge a very large capacitor into the SW
output too quickly).
Action: SW system tristates output amplifier until bus level
becomes normal.
UV Undervoltage: Indicates that the output voltage is less than the
programmed value, but not in the voltage foldback mode.
Action: Opens relays and displays error message.
ROC Redundant Over Current: The RMS value of the output current
has exceeded the maximum capacity of the SW.
Action: Opens relays and displays error message.
RMS_OV Monitors the external input in the “External Direct” mode to ensure
that it does not exceed 5.2 VRMS.
Action: Opens relays, displays error message, and sets
VPROGRAM to zero volts.
FLT_IN Fault-Input from Slave chassis: Represents the logical OR of
several faults.
Action: Opens relays, displays error message, and sets
VPROGRAM to zero volts. Clearing the error message
sends a fault reset to the Slave chassis. The particular
Slave chassis that had the fault will then extinguish its
fault indicator.
Table 3–6 Fault Description and Action (FR2)
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RLY156,RLY312 Used for internal monitoring only.
RLY_FLT The open relay did not respond to the open/close command within
500 mSec.
Action: Programs the output to zero and attempts to change relay
state; displays error message and shuts off SW if output
relay hasn’t changed state within 500 mSecs. If unable to
clear error message, a hazardous condition may exist. Use
caution; voltage may be present at the output terminals.
Table 3–7 Fault Description and Action (FR3)