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4.0 OPERATING INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.1 Initial System Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.2 Basic Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.2.1 Momentary Tie - Load Transfers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.2.2 Normal Transfer Operation Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.2.3 Maintenance Procedures - Isolating Each UPS System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.2.4 Isolating a UPS System for Maintenance - Combined Loads Operation. . . . . . . . . . . . . . . . . 26
4.2.5 Transfer of Load Between Two Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.2.6 Returning an Isolated System to Normal Operation - End Combined Loads Operation. . . . 27
4.2.7 Maintenance Procedures - Maintaining Power-Tie Components . . . . . . . . . . . . . . . . . . . . . . 27
4.2.8 Maintenance Procedures - Tie Control Logic Components . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.2.9 Abnormal Operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
4.2.10 Trouble Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
4.2.11 Continuous Tie-Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.2.12 Isolation for Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.2.13 Operation Scenarios/Transfer Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
FIGURES
Figure 1 Basic Dual-Bus Power-Tie one-line diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Figure 2 Power-Tie systems - fault isolation issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Figure 3 Power-Tie systems - control interface diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Figure 4 Power-Tie system one-line diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 5 Control panel layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 6 Power-Tie system - fault isolation issues. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 7 Power-Tie systems - fault tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 8 Power-Tie system one-line diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Figure 9 From start-up to normal operation, loads to be split between two distribution feeders . . . . . . . 33
Figure 10 From combined loads operation to loads split between two feeders . . . . . . . . . . . . . . . . . . . . . . . 33
Figure 11 From continuous tied systems to loads split between two systems . . . . . . . . . . . . . . . . . . . . . . . 33
Figure 12 Transfer both load feeders to one UPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 13 Both feeders on one system to normal operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 14 Transfer 100% load on one system to 100% load on a second system (a two-step operation) . . . 34
Figure 15 Normal split load operations to Continuous Tie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure 16 Continuous Tie to normal split load operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure 17 Continuous Tie to load on one system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure 18 Load on one system to Continuous Tie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Figure 19 One system in bypass to both feeders combined on remaining operational system . . . . . . . . . . 36
Figure 20 One system in bypass to Continuous Tie operation (Option 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Figure 21 One system in bypass to Continuous Tie operation (Option 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . 37