MITSUBISHI ELECTRIC 9900B SERIES UPS
MITSUBISHI
ELECTRIC
9900B SERIES UPS
OWNERS / TECHNICAL MANUAL
Page Number:
6-7
Table 6.1 (continuation)
Code
indication
(Note 3)
Status
message
Meaning
Guidance
Buzzer
External
relay contact
(Note 1)
Failure
lamp
(Note 2)
UF352
CONTROL
POWER SUPPLY
ABNORMAL
Backup control power
supplies exhibit abnormal
condition.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF363
UPS CONTROL
CIRCUIT ERROR
Synchronization status
signal is being received for a
considerable time.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF371
UPS CONTROL
CIRCUIT ERROR
Minor communication error
during parallel operation.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF372
UPS CONTROL
CIRCUIT ERROR
Unable to synchronize the
inverter output and the
bypass voltage.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF374
UPS CONTROL
CIRCUIT ERROR
Cable disconnection in the
parallel interface board.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF375
UPS CONTROL
CIRCUIT ERROR
Unable to achieve
synchronization for parallel
operation.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF376
UPS CONTROL
CIRCUIT ERROR
No control response from
another UPS although its
detection is possible.
CALL
SERVICE
ENGINEER
Intermittents
ound
Minor
Flicker
UF377
UPS CONTROL
CIRCUIT ERROR
Overload detection signal is
being received continuously
for a considerable time.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF378
UPS CONTROL
CIRCUIT ERROR
No answer for sending
synchronizing signal.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF379
UPS CONTROL
CIRCUIT ERROR
Abnormal clock speed of the
parallel control board
processor.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF401
52S ABNORMAL
Error to close the contactor
52S.
CALL
SERVICE
ENGINEER
Continuous
sound
Major
Lit on
UF402
52S ABNORMAL
Error to open the contactor
52S.
CALL
SERVICE
ENGINEER
Continuous
sound
Major
Lit on
UF420
52L OPERATION
ERROR
Load circuit breaker 52L
opened during inverter
operation.
CHECK 52L
Continuous
sound
Major
Lit on
UF451
52S ABNORMAL
Contactor 52S failed during
load transfer from inverter to
bypass.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
UF452
CB3 ABNORMAL
Contactor CB3 is not
working properly.
CALL
SERVICE
ENGINEER
Intermittent
sound
Minor
Flicker
(Note 1) 1) "Major" is defined as a major failure. The load is transferred from the inverter circuit to
the static bypass line.
2) "Minor" is defined as a minor failure. The UPS continues to operate normally, but the
cause of alarm must be identified.
(Note 2) Indicates one of two possible LED illumination patterns - continuously on (lit on) or
intermittent (flicker).
Summary of Contents for 9900B Series
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