Relays are the logic elements, which initiate the

(1)

Elective Course 1 Introduction to

Protection System

(2)

Relays

Relays are the logic elements, which initiate the

tripping and closing operations. There are many types

of relays according to its function, input, Operating

principle or structure, and Performance Characteristic.

(3)

Relays

Function Input Operating principle Performance

or structure Characteristic

(4)

Current Power Frequency Flow Information

Voltage Pressure Temperature Vibration

Relay - Inputs

(5)

Relay - Inputs

The above classifications are based on the ANSI

standard C 37.90.

(6)

Current balance Product Sold state Static Thermal

Percentage Multi-restraint Microprocessor Electromechanical

Relay - Operating principle or

structure

(7)

Relay - Operating principle or

structure

The above classifications are based on the ANSI

standard C 37.90.

(8)

Distance Inverse time Under-voltage Ground or phase Phase comparison Segregated phase

Directional-overcurrent Definite time Overvoltage High or low speed Directional-comparison

Relays are the logic elements, which initiate the

Elective Course 1 Introduction to

Protection System

Relays

Relays are the logic elements, which initiate the

tripping and closing operations. There are many types

of relays according to its function, input, Operating

principle or structure, and Performance Characteristic.

Relays

Function Input Operating principle Performance

or structure Characteristic

Relay - Inputs

Relay - Inputs

The above classifications are based on the ANSI

standard C 37.90.

Relay - Operating principle or

structure

Relay - Operating principle or

structure

The above classifications are based on the ANSI

standard C 37.90.

Relay - Performance

Characteristic

Relay - Performance Characteristic

The above classifications are based on the ANSI

standard C 37.90.