ABB REL 356

ABB REL 356 Current Differential Protection
Page ix
Guide to Figures
Section 1 Product Overview and Specifications
Figure 1-1 Fault Recognition .......................................................................................................................... 1-2
Section 2 Installation, Operation and Maintenance
Figure 2-1 Backplane..................................................................................................................................... 2-2
Figure 2-2 RS232/PONI Communication Interface Device ........................................................................... 2-14
Figure 2-3 Layout of REL 356 Modules Within Inner and Outer Chassis ...................................................... 2-20
Figure 2-4 Block Diagram of REL 356 Relay ................................................................................................ 2-21
Section 3 Settings and Applications
Figure 3-1 Ratio of I
3
F
min
/I
F
Gmin
vs. C0 (C1 = 0.1, C2 - 0.7) ....................................................................... 3-10
Figure 3-2 Tapped Load Application............................................................................................................ 3-18
Figure 3-3 Setting Example-Tapped Load Application ................................................................................ 3-34
Section 4 Measuring Elements and Operational Logic
Figure 4-1 IT Filter Output for an A-G Fault ................................................................................................... 4-1
Figure 4-2 Current Differential Logic ............................................................................................................... 4-2
Figure 4-3 Operating Characteristic................................................................................................................ 4-3
Figure 4-4 Data Frame ................................................................................................................................... 4-4
Figure 4-5 Open Breaker Trip......................................................................................................................... 4-5
Figure 4-6 Stub Bus Trip................................................................................................................................ 4-6
Figure 4-7 Phase Selector ............................................................................................................................. 4-8
Figure 4-8 Mho Characteristic for Phase to Ground Faults ........................................................................... 4-10
Figure 4-9 Mho Characteristic for Three Phase Faults ................................................................................. 4-11
Figure 4-10 Mho Characteristic for Phase to Phase Faults .......................................................................... 4-11
Figure 4-11 Blinders for the Out of Step Logic ............................................................................................. 4-12
Guide to Figures