Appendix FRCC regional application of the term transmission Protection Systems This is a clarification of the FRCC regional application of the term transmission Protection Systems as used in the PRC -series Reliability Standards Since it is impractical to document every situation for Protection Systems, examples are provided for general clarification. Protection Systems, as defined by this Appendix, are included in the definition of transmission Protection Systems for application of NERC PRC-series Reliability Standards. Protection Systems included in the application of the term transmission Protection Systems : o Protection Systems that detect faults on transmission elements (lines, buses, transformers, etc.) identified as being included in the ulk Electric System () and trips an interrupting device that interrupts current supplied directly from a Element.Protection Systems that trip Elements (as established in the FRCC Definition). Protection Systems excluded from the application of the term transmission Protection Systems : o Protection Systems that do not trip Elements. o Generating plant control and operation functions which include relays and systems that control and protect the unit for boiler, turbine, environmental, and/or other plant restrictions. The following examples are provided for clarification of the definition of transmission Protection Systems. In general, a two step process is followed: 1. Identify which Elements are considered and which Elements are considered non-. 2. Determine which Protection Systems detect faults on transmission elements (lines, buses, transformers, etc.) identified as being included in the ulk Electric System () and trip an interrupting device that interrupts current supplied directly from a Element. Version 23 Draft 48/1216/2010 Approved by the FRCC oard of Directors Effective Dates: FRCC Definition, Appendix A: Clarification to the FRCC ulk Electric System () Definition for Radial Transmission Elements or Systems Exclusion, and Appendix C: Adverse Reliability Impact Study Requirements: 1 st day of the 3 rd calendar quarter following regulatory approval. Appendix : FRCC regional application of the term transmission Protection Systems : 1 st day of the 7 th calendar quarter following regulatory approval.
2. Identify which Protection Systems trip Elements and which Protection Systems do not trip Elements. Note: Isolation/disconnect switches are omitted in these examples (i.e., breaker disconnects, transformer isolation, etc.) except where such switches are relevant to operation of transmission Protection Systems. Page 2 of 7
Example One: A Line 1 Excluded Radial System (Non-) * Motor-Operated Disconnect Switch or Circuit Switcher or reaker * LOAD Circuit breakers A and and Transmission Line 1 are part of the. Protection Systems for Transmission Line 1 including the radial tap is aare transmission Protection Systems.. The transformer and associated switches are not part of the. Protection Systems for the transformer are not transmission Protection Systems because the transformer is not a Element. Protection Systems for the transformers are transmission Protection Systems if they trip line 1 for a transformer fault (e.g. if the transformer high side disconnecting device is a motoroperated disconnect switch, then the transformer protection will likely transfer trip breakers A and ). Protection Systems for the transformers are not transmission Protection Systems if they will not trip line 1 for a transformer fault (e.g. if the transformer high side disconnecting device is a circuit switcher or breaker, then there may be no transfer trip of breakers A and ). Protection Systems that initiate a transfer trip of line 1 are transmission Protection Systems. Page 3 of 7
Example Two: Non- Line 1 A Line 2 * * C D * Motor-Operated Disconnect Switch or Circuit Switcher or reaker E F G Circuit breaker A and Transmission Lines 1 & 2 are part of the. The transformers and associated switches are not part of the. Protection Systems for Transmission Lines 1 & 2 are transmission Protection Systems. Protection Systems for the transformer are not transmission Protection Systems because the transformer is not a Element. Protection Systems for the transformers are transmission Protection Systems if they trip lines 1 or 2 for a transformer fault (e.g. transformer high side disconnecting device motor-operated disconnect switch). Protection Systems for the transformers are not transmission Protection Systems if they will not trip lines 1 or 2 for a transformer fault (e.g. transformer high side disconnecting device circuit switcher or breaker). Protection Systems that initiate a transfer trip of either line 1 or 2 is a transmission Protection Systems. Page 4 of 7
Example Three: Line 2 Line 3 A C West us Line 4 East us D E F Non- Line 1 LOAD Lines 2, 3 and 4 and the substation, including the East and West bus, are part of the. Line 1, including the transformer and the associated switches, is radial and not part of the. Protection System for Line 1 is a transmission Protection System since the line protection will trip breakers D and E and the bus section between breakers D and E which are part of the, even though line 1 is not part of the. The Protection System for the transformer is a transmission Protection System if it transfer trips breakers D and E. The Protection System for the bus/line between breakers D and E and the associated tap is a transmission Protection System. Protection Systems for the transformer are not transmission Protection Systems because the transformer is not a Element. Page 5 of 7
Example Four: Line 1 A Line 2 C Substation 1 D Excluded Radial System (Non-) Switch A Switch Line 3 Line 4 E F G Substation 2 LOAD Unregistered Generation Transmission Lines 1 & 2 and circuit breakers A,, C and D are part of the. Circuit breakers E, F and G, Transmission Lines 3 & 4 and the transformers are not part of the. The Protection Systems for the bus sections between breakers and D and breakers C and D including the bus sections connecting to the source side of Switch A and Switch are transmission Protection Systems. Protection Systems for Transmission Lines 3 & 4 would trip breakers and bus sections at substation 1, which are part of the even though the line itself is not; therefore, the Protection Systems are transmission Protection Systems. Page 6 of 7
The breaker failure protection at substation 2 for breakers E and F, if it transfer trips to substation 1, is a transmission Protection System because it would trip portions of substation 1 that are part of the. Page 7 of 7