Overview
The “Reyrolle 7SR242 Duobias” transformer protection device has been specifically designed to provide protection, control and monitoring for two winding transformers.
For more detailed information on “7SR242 Duobias” relay, refer to Reyrolle devices documents.
To see other supported Reyrolle relays, click here.
Function Diagram: 7SR242n-2aAnn-0AA0 Relay
Function Diagram: 7SR242n-2aAnn-0BA0 Relay
Function Diagram: 7SR242n-2aAnn-0CA0 Relay
Summary of 7SR24 Relay Configurations
Current Protection Functions
Differential Protection (87)
Biased Differential Characteristic
Functional Diagram for Biased Current Differential Protection (87BD)
Technical Data for Function 87BD
Differential Highset Characteristic
Logic Diagram for High Set Current Differential Protection (87HS)
Technical Data for Function 87HS
Phase Overcurrent (51, 50)
Logic Diagram for Instantaneous Over-current Element (50)
Technical Data for Function 50
Logic Diagram for Time Delayed Overcurrent Element (51)
Technical Data for Function 51
Derived Earth Fault (50N, 51N)
Logic Diagram for Instantaneous Derived Earth Fault Element (50N)
Technical Data for Function 50N
Logic Diagram for Derived Time Delayed Earth Fault Protection (51N)
Technical Data for Function 51N
Measured Earth Fault (50G, 51G)
Logic Diagram for Measured Instantaneous Earth-fault Element (50G)
Technical Data for Function 50G
Logic Diagram for Time Delayed Measured Earth Fault Element (51G)
Technical Data for Function 51G
High Impedance Restricted Earth Fault (64H)
Logic Diagram for High Impedance REF (64H)
Technical Data for Function 64H
Open Circuit (46BC)
Logic Diagram for Open Circuit Function (46BC)
Technical Data for Function 46BC
Negative Phase Sequence Overcurrent (46NPS)
Logic Diagram for Negative Phase Sequence Overcurrent (46NPS)
Technical Data for Function 46NPS
Under-Current (37, 37G)
Logic Diagram for Undercurrent Detector (37, 37G)
Technical Data for Function 37, 37G
Thermal Overload (49)
Logic Diagram for Thermal Overload Protection (49)
Technical Data for Function 49
Operate Time (t) Calculation for Function 49
Thermal Overload Protection (49) Curves
Voltage Protection Functions
Over Fluxing (24)
Inverse Over-fluxing Characteristic (24IT)
Logic Diagram for Overfluxing Elements (24)
Technical Data for Function 24
Under/Over Voltage (27/59)
Logic Diagram for Under/Over Voltage Elements (27/59)
Technical Data for Function 27/59
Neutral Overvoltage (59N)
Logic Diagram for Neutral Overvoltage Element (59N)
Technical Data for Function 59N
Under/Over Frequency (81)
Logic Diagram for Under/Over Frequency (81)
Technical Data for Function 81
Supervision Functions
Circuit Breaker Failure (50BF)
Logic Diagram for Circuit Breaker Fail Protection (50BF)
Technical Data for Function 50BF
Trip/Close Circuit Supervision (74TCS/74CCS)
Logic Diagram for Trip Circuit Supervision Feature (74TCS)
Logic Diagram for Close Circuit Supervision Feature (74CCS)
Technical Data for Function 74TCS/74CCS
Inrush Detector (81HBL2)
Logic Diagram for Inrush Detector (81HBL2)
Technical Data for Function 81HBL2
Over Fluxing Detector (81HBL5)
Logic Diagram for Over Fluxing Detector (81HBL5)
Technical Data for Function 81HBL5
General
IEC IDMTL & ANSI Curves
IEC IDMTL Curves (Time Multiplier=1)
ANSI IDMTL Operate Curves (Time Multiplier=1)
ANSI Reset Curves (Time Multiplier=1)
