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Protection Relay - Coggle Diagram
Protection Relay
Type of Relays/Classification
Protection Relay
Brain
Current and Voltage Transformer(CT&PT)
Eye and Ear
Auxiliary Power(Battery)
Heart
Switching Device-Circuit Breaker (CB)
Muscles
Alarm
Mouth
AC and DC Wiring
Nerves
Principle of Relay
Monitor continuously system parameters
No need for action
Must trip very quick
Not operate wrongly
Must have discrimination/stability
Purposes of relay
To sound an alarm
To disconnect the abnormal part
To localize the fault
To minimize hazard to personnel
Type of Relays
Electromagnetic Relay
Analog Relay
Digital Relay
Numerical Relay
Basic Relay Testing at Site
Pick-up current test
Tripping time test
Tripping of Circuit Breaker (CB) from relay
Communication signal test to control system
Relay Calibration Test
Type Tests
Routine Factory Production Tests
Commissioning Tests
Periodic Maintenance Tests
Relays can be classify by TWO
By construction
By relay operation
What is the relay?
automatic devices which senses an abnormal condition of electrical circuit and closes its contacts.
Relay Power Supply
direct-current power supply
advantages
do not require Big UPS
does not suffer on harmonics
has high reliable
Maintenance cost is less
DC supply for Long distance without voltage dropping
Control Circuits are consist of many digital devices