P50 Agile P153
6 Protection Functions
P153/EN M/B
6-13
time. If the fault current has not been interrupted following a set time delay from circuit breaker trip
initiation, the CBF protection will operate, whereby the upstream circuit breakers are back-tripped to
ensure that the fault is isolated.
CBF operation can also reset all start output contacts, ensuring that any blocks asserted on upstream
protection are removed.
2.8.1
Circuit Breaker Fail Implementation
Circuit Breaker Failure Protection is implemented in the CB FAIL column of the relevant settings
group.
The circuit breaker failure protection incorporates
CB Fail Timer
. For any protection trip, the
CB Fail
Timer
is started, and normally reset when the circuit breaker opens to isolate the fault. If breaker
opening is not detected, the CB Fail Timer times out and close an output contact assigned to breaker
fail (using the I/O assignment feature). This contact is used to back-trip upstream switchgear,
generally tripping all infeeds connected to the same busbar section.
2.8.2
Circuit Breaker Fail Logic
Figure 6: CB Fail Logic
CBF elements
CB Fail Timer
can be configured to operate for trips triggered by protection elements
within the device or via an external protection trip. The latter is achieved by allocating one of the opto-
isolated inputs to CBF Init signal using the I/O Mask feature.
It is possible to reset the CBF from a breaker open indication from a protection reset. In these cases
resetting is only allowed provided the undercurrent elements have also been reset. The resetting
options are summarised in the following table:
CBF function Reset options
Description
I<
CBF function will reset when the phase currents and earth current is less than
set current
Summary of Contents for Agile P50 Series
Page 3: ...P50 Agile P153 1 Introduction P153 EN M B 1 1 INTRODUCTION CHAPTER 1...
Page 4: ...1 Introduction P50 Agile P153 1 2 P153 EN M B...
Page 10: ...1 Introduction P50 Agile P153 1 8 P153 EN M B...
Page 11: ...P50 Agile P153 2 Safety Information P153 EN M A 2 1 SAFETY INFORMATION CHAPTER 2...
Page 22: ...Chapter 2 Safety Information P50 Agile P153 2 12 P153 EN M A...
Page 23: ...P50 Agile P153 3 Hardware Design P153 EN M B 3 1 HARDWARE DESIGN CHAPTER 3...
Page 24: ...3 Hardware Design P50 Agile P153 3 2 P153 EN M B...
Page 32: ...3 Hardware Design P50 Agile P153 3 10 P153 EN M B...
Page 33: ...P50 Agile P153 4 Front Panel P153 EN M B 4 1 FRONT PANEL CHAPTER 4...
Page 34: ...4 Front Panel P50 Agile P153 4 2 P153 EN M B...
Page 39: ...P50 Agile P153 5 Configuration P153 EN M B 5 1 CONFIGURATION CHAPTER 5...
Page 40: ...P50 Agile P153 5 Configuration P153 EN M B 5 2...
Page 150: ...P50 Agile P153 5 Configuration P153 EN M B 5 112...
Page 151: ...P50 Agile P153 6 Protection Functions P153 EN M B 6 1 PROTECTION FUNCTIONS CHAPTER 6...
Page 152: ...6 Protection Functions P50 Agile P153 6 2 P153 EN M B...
Page 168: ...7 Protection Parameter Settings P50 Agile P153 7 2 P153 EN M B...
Page 189: ...P50 Agile P153 8 Monitoring Control P153 EN M B 8 1 MONITORING CONTROL CHAPTER 8...
Page 190: ...8 Monitoring Control P50 Agile P153 8 2 P153 EN M B...
Page 207: ...P50 Agile P153 9 SCADA Communications P153 EN M B 9 1 SCADA COMMUNICATIONS CHAPTER 9...
Page 208: ...12 SCADA Communications P50 Agile P153 9 2 P153 EN M B...
Page 220: ...12 SCADA Communications P50 Agile P153 9 14 P153 EN M B...
Page 221: ...P50 Agile P153 10 Installation P153 EN M B 10 1 INSTALLATION CHAPTER 10...
Page 222: ...10 Installation P50 Agile P153 10 2 P153 EN M B...
Page 234: ...13 Commissioning Instructions P50 Agile P153 13 2 P153 EN M B...
Page 242: ...12 Maintenance and Troubleshooting P50 Agile P153 12 2 P153 EN M B...
Page 250: ...12 Maintenance and Troubleshooting P50 Agile P153 12 10 P153 EN M B...
Page 252: ...13 Technical Specifications P50 Agile P153 13 2 P153 EN M B...
Page 263: ...P50 Agile P153 14 Wiring Diagrams P153 EN M B 14 1 WIRING DIAGRAMS CHAPTER 14...
Page 264: ...14 Wiring Diagrams P50 Agile P153 14 2 P153 EN M B...
Page 267: ......