EXAMPLE 10 Description: A Fault occurs on the high-side of the distribution transformer (TX A in green) and a Protection System located at Substation A (with a primary purpose to detect Faults on TX A) operates to open up non-BES breaker A, however breaker A does not open. The Protection System then attempts to initiate a breaker failure scheme, also located Substation A, which also fails to open BES Breaker B (it does however open BKR C and BKR D). However, there is also a power line carrier at Substation A that sends a blocking signal to Substation C relays waiting for Breaker B to operate. If Breaker B does not operate in the time allotted, relays at Substation C will open the BES breakers at Substation C as shown in the illustration. Questions/Findings: PRC-005 Applicable Is the power line carrier located at Substation A part of a PRC-005 Protection System? Task Force Answer: FRCC Answer: BES Cyber Assets present: Is the power line carrier located at Substation A part of a BES Cyber System? Task Force Answer: FRCC Answer:
EXAMPLE 10 Description: A Fault occurs on the high-side of the distribution transformer (TX A in green) and a Protection System located at Substation A (with a primary purpose to detect Faults on TX A) operates to open up non-BES breaker A, however breaker A does not open. The Protection System then attempts to initiate a breaker failure scheme, also located Substation A, which also fails to open BES Breaker B (it does however open BKR C and BKR D). However, there is also a power line carrier at Substation A that sends a blocking signal to Substation C relays waiting for Breaker B to operate. If Breaker B does not operate in the time allotted, relays at Substation C will open the BES breakers at Substation C as shown in the illustration. Questions/Findings: PRC-005 Applicable Is the power line carrier located at Substation A part of a PRC-005 Protection System? Task Force Answer: FRCC Answer: BES Cyber Assets present: Is the power line carrier located at Substation A part of a BES Cyber System? Task Force Answer: FRCC Answer: