Siemens Reyrolle 5 7SR5420 Transformer Differential Protection Numerical Relay

The Siemens Reyrolle 5 7SR5420 is a transformer protection relay designed for 2-winding transformer differential protection. It belongs to the Reyrolle 7SR54 family and is suitable for modern substation applications with integrated monitoring, control, and communication capabilities.

The device supports multiple product functions, including fault recording, sequence-of-events recording, circuit breaker monitoring, and logic configuration. It provides flexible parameter handling with multiple parameter sets and supports operational control and monitoring functions.

Siemens Reyrolle 5 7SR5420 Inputs and Outputs

8 CT + 16 BI + 8 BO (standard configuration)

Communication

Front USB port, rear RS485, and Ethernet communication interfaces are supported within the Reyrolle 5 platform.

Housing

S8 enclosure with withdrawable design.

Product Details

Number of function keys: 7
Number of LEDs: 28

Product Functions

• Type of measured value detection (standard): Yes
•  Expanded measured values (min./max./mean): Yes
•  Switching statistics: Yes
•  Circuit breaker monitoring: Yes
•  Logic editor: Yes
•  Control: Yes
• Fault recording (analog and digital): Yes
•  Sequence-of-events recorder: Yes
•  Monitoring: Yes
•  Number of parameter sets: 4\
•  Parameter set switchover: Yes
•  Circuit breaker test: Yes

Protection Functions

• Three-pole tripping: Yes
•  Synchrocheck (ANSI 25): No
•  Undervoltage protection (ANSI 27): No
•  Directional power monitoring (ANSI 32): No
•  Forward power supervision (ANSI 32F): No
•  Reverse power protection (ANSI 32R): No
•  Undercurrent protection (ANSI 37): Yes
•  Unbalance protection (ANSI 46): Yes
•  Negative sequence overcurrent (ANSI 46): Yes
•  Phase rotation supervision (ANSI 47): No
•  Negative sequence overvoltage (ANSI 47): No
•  Thermal overload protection (ANSI 49): Yes
•  Instantaneous overcurrent (ANSI 50/50N): Yes
•  Switch on to fault (ANSI SOTF): No
•  Arc protection (ANSI AFD): Yes
•  Sensitive earth fault (ANSI 50Ns): No
•  Circuit breaker failure protection (ANSI 50BF): Yes
•  Time delayed overcurrent (ANSI 51/51N): Yes
•  Dynamic response changeover (ANSI 51C): Yes

Monitoring Functions

Measured values (current, voltage)
Fault recording and event logs

Sequence-of-events recording

Communication

• IEC 61850
• IEC 60870-5-103
• MODBUS-RTU
• DNP 3.0

Applications

2-winding transformer differential protection in MV and HV systems

Benefits

Integrated monitoring and control functions
Multiple parameter sets for flexible operation
Reliable protection with standard ANSI functions
User interface with LEDs and function keys for easy operation