Electrical Consultants relay coordination and relay testing ETAP
₹ 20,000/PieceRelay Type: Electromagnetic Relay, Static Relay, Electromechanical Relay, Numerical Relay
Service Scope: Site Supervision, Testing And Commission, Design, Third Party Audit, Energy Audit, Detail Engineering
Relay Coordination and Relay Testing (ETAP Studies)
Relay Coordination Study and Relay Testing are critical activities in power system protection to ensure selective, reliable, and fast fault clearance.
1. Relay Coordination Study Using ETAP Objective
To establish proper settings and coordination between protective devices so that only the faulted section is isolated while maintaining system stability and continuity.
Scope of Study
Overcurrent Relay Coordination (50/51)
Earth Fault Relay Coordination (50N/51N)
Differential Protection (87)
Distance Protection (21)
Transformer Protection
Motor Protection
Generator Protection
Busbar Protection
ETAP Study Methodology Data Collection
Single Line Diagram (SLD)
Transformer ratings and impedance
Generator data
Motor ratings
Cable sizes and lengths
CT/PT ratios
Circuit breaker ratings
Existing relay settings
System Modeling
Develop network model in ETAP
Enter equipment parameters
Verify system connectivity
Short Circuit Analysis
IEC 60909 / ANSI standards
Determine maximum and minimum fault levels
Calculate:
3-Phase Fault
Line-to-Line Fault
Line-to-Ground Fault
Double Line-to-Ground Fault
2. Relay Testing Purpose
To verify relay operation according to protection philosophy and ETAP-calculated settings.
Types of Relay Testing A. Secondary Injection Test Equipment
Omicron CMC
Megger SMRT
Doble F6150
Tests Performed
Pickup Test
Drop-off Test
Timing Test
Directional Test
Harmonic Restraint Test
Differential Stability Test
Verification
Current pickup accuracy
Operating time accuracy
Relay logic operation
Alarm and trip functions
B. Primary Injection Test Purpose
Verify complete protection circuit including:
CTs
Relay
Trip Circuit
Circuit Breaker
Tests
Current Injection
CT Polarity Verification
CT Ratio Verification
Breaker Trip Verification
Common Protection Relays Tested Feeder Protection Relay
Functions:
50/51 Overcurrent
50N/51N Earth Fault
27 Under Voltage
59 Over Voltage
81 Under/Over Frequency
Transformer Relay
Functions:
87T Differential
REF (64)
Buchholz Alarm/Trip
Temperature Protection
Overcurrent Backup
Motor Relay
Functions:
Overload (49)
Locked Rotor (48)
Negative Sequence (46)
Earth Fault (50G/51G)
Generator Relay
Functions:
Differential (87G)
Reverse Power (32)
Loss of Excitation (40)
Over/Under Voltage (59/27)
Over/Under Frequency (81)