Multi-end differential and distance protection relay Siemens Power Transmission Distribution

7SD5 relay provides full scheme differential protection and incorporates all functions usually required for the protection of power lines. It is designed for all power and distribution levels and protects lines with two up to six line ends, to provide high-speed and phase-selective fault clearance.

Application
• Differential protection with phase-segregated measurement
• Sensitive measuring stage for high-resistance faults
• Non-switched distance protection with 6 measuring systems
• High resistance ground (earth)-fault protection for 1 and 3-pole tripping
• Phase-selective intertripping
• Tele (pilot) protection
• Weak-infeed protection
• Fault locator
• Power swing detection/tripping
• 3-stage overcurrent protection
• STUB bus protection
• Switch-onto-fault protection
• Over/undervoltage protection
• Over/underfrequency protection
• Auto-reclosure
• Synchro-check
• Breaker failure protection
• Overload protection
• Lockout function

Digital communication via
• fiber-optic cables
• digital communication networks
• pilot wires or ISDN connections

More specifications...