6 Protection Functions
P50 Agile P153
6-14
P153/EN M/B
CBF function Reset options
Description
CB Open + I<
CBF function will reset when both conditions are satisfied:
•
CB is open (i.e. CB(52B) status is active)
•
The phase currents and earth current is less than set current
Prot Reset + I<
CBF function will reset when both conditions are satisfied:
•
Protection is reset
•
Phase currents and earth current is less than set current
CB Open
CBF function will reset when CB is open (i.e. CB(52B) status is active)
The
Remove I> Start
and
Remove IN>
Start settings are used to remove starts issued from the
overcurrent and earth elements respectively following a breaker fail time out. The start is removed
when the cell is set to 'Enabled'
.
2.9
Cold Load Pickup Function
When a feeder circuit breaker is closed in order to energise a load, the current levels that flow for a
period of time following energisation may be far greater than the normal load levels. Consequently,
overcurrent settings that have been applied to provide overcurrent protection may not be suitable
during this period of energisation (cold load), as they may initiate undesired tripping of the circuit
breaker. This scenario can be prevented with Cold Load Pickup (CLP) functionality.
The Cold Load Pickup (CLP) logic works by either:
•
Inhibiting one or more stages of the overcurrent protection for a set duration
•
Raising the overcurrent settings of selected stages, for the cold loading period.
The CLP logic therefore provides stability, whilst maintaining protection during the start-up.
Cold Load Pickup Protection is implemented in the
COLD LOAD PICKUP
column of the relevant
settings group.
This function acts upon the following protection functions:
•
All overcurrent stages
•
All Earth Fault stages
The principle of operation is identical for the 3-phase overcurrent protection and Earth Fault
overcurrent protection.
CLP operation occurs when the circuit breaker remains open for a time greater than
tcold
and is
subsequently closed. CLP operation is applied after
tcold
and remains for a set time delay of
tclp
following closure of the circuit breaker. The status of the circuit breaker is provided by means of the
CB auxiliary contacts. Whilst CLP operation is in force, the CLP settings are enabled. After the time
delay
tclp
has elapsed, the normal overcurrent settings are applied and the CLP settings are disabled.
If desired, instead of applying different current setting thresholds for the cold load time, it is also
possible to completely block the overcurrent operation during this time, for any of the overcurrent
stages.
2.9.1
Cold Load Pickup Logic
The CLP logic is in operation when CLP is enabled AND CLP is initiated from a CB open condition
after the
tcold
period has elapsed. The CLP logic becomes inactive when CLP is disabled or when
there is a CB closed condition.
tcold
and
tclp
are initiated using the CB status signal produced by
connecting CB NO auxiliary contact from the circuit breaker. The CLP logic gets driven from a single
breaker contact.
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: ......