ABB TruONE ATS Installation And Operating Instruction page 25

3 4 O X _ 3 0 - 1 6 0 0 r e v. B / 1 S C C 3 0 3 0 1 1 M 0 2 0 1
2.5.1.2 Source 2 Priority (No generator)
Switching sequence summary:
• An anomaly occurs on the source 2
• Override momentary S2 outage delay
• Transfer from S2 to S1 delay
• Pre-transfer signal on
• Load shed signal on
• Pre-transfer S2 to S1 delay
• Load shed delay
• Transfer switch to the position O (only
with delayed transition I-O-II type and
at least one phase exists in source 2)
• Center-Off delay (only with delayed
transition I-O-II type, delay is zero when
all phases are missing in source 2)
• Transfer switch to the position I
(source 1)
• Post-transfer S2 to S1 delay
• Pre-transfer signal off
Retransfer sequence summary:
• The source 2 is restored
• Transfer from S1 to S2 delay
• Pre-transfer signal on
• Pre-transfer S1 to S2 delay
• Transfer switch to the position O (only
with delayed transition I-O-II type)
• Center-off delay (only with Delayed tran-
sition I - O - II type)
• Transfer switch to the position II
(source 2)
• Load shed signal off
• Post-transfer S1 to S2 delay
• Pre-transfer signal off
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