ABB Zenith ZBTS T Series, Installation And Operating Instruction, Page: 54 / 112

54 Zenith ZBTS T-series 100-1200A, I N S TA LL ATI O N A N D O PER ATI N G I N S TR U C TI O N
1
Alarms, continued from previous page
Message Fault Action
S2 undervoltage Voltage of source 2 is under the
threshold level set in parameter “Drop-
out voltage, lower threshold“
Check the correlation between power
source and device configuration
S2 overvoltage Voltage of source 2 is over the
threshold level set in parameter “Drop-
out voltage, upper threshold“
Check the correlation between power
source and device configuration
S2 phase missing One or two phases of source 2 are
missing
Check the power source and
connections
S2 unbalance Phases of source 2 are not symmetric Check the power source
S2 phase rotation Phase rotation of source 2 is different
from the value of parameter “Phase
sequence“
Connect the phases according to the
configuration
S2 invalid frequency Frequency of source 2 is out of range
set in parameters “Drop-out frequency,
upper threshold“ and “Drop-out
frequency, lower threshold“
Check the correlation between power
source and device configuration
S2 neutral
disconnected
Neutral is disconnected from source 2.
Note: The loss of neutral will be
detected in 3 phase distribution
systems with unbalanced loads
Alarm is active and transfer operations
disabled as long as the frequency
difference is above the accepted level
Frequency Difference Frequency difference of voltage
sources is greater than 3 Hz while in-
phase monitor is on
Check connection of neutral in source 2
and that the corresponding power
distribution system parameter is set
correctly
High current alarm Measured current is higher than ten
times the nominal value
Alarm is active and transfer operations
disabled as long as the high current
status remains
Open I failure, Alarm
LED blinking Switch transfer from position I to O or
II failed
Reset alarm by pressing Auto button or
via menu page Operation / Alarm Reset
Close I failure, Alarm
LED blinking Switch transfer to position I failed Reset alarm by pressing Auto button or
via menu page Operation / Alarm Reset
Open II failure, Alarm
LED blinking Switch transfer from position II to O or
I failed
Reset alarm by pressing Auto button or
via menu page Operation / Alarm Reset
Close II failure, Alarm
LED blinking Switch transfer to position II failed Reset alarm by pressing Auto button or
via menu page Operation / Alarm Reset
Switch position alarm,
Alarm LED on More than one switch position
indication inputs are activated
Switch service needed
Continued on the next page