Siemens SIPROTEC 5 7SS85 Busbar Protection Relay

Centralized busbar protection with: ، 20 three-phase current measuring points ، 4 three-phase voltage measuring points ، 26 bays (feeders, couplers, bus-section disconnections) ، 4 bus zones with measurement ، 4 couplers with 1 or 2 current transformers ، 2 auxiliary busbars without measurement ، Phase-selective measurement and display ، Selective tripping of faulty bus zones ، Disconnector-independent check zone ، Shortest tripping times (<7 ms) ، High stability during external faults, including transformer saturation ، Freely adjustable operate curve and additional high-sensitivity curves ، Fast recognition of internal and external faults (2 ms) ، Compatible with closed iron core or linearized CTs ، Adaptable CT ratios per parameterization ، Three measurement methods for minimum tripping time and max stability ، Circuit-breaker failure protection integrated ، Extensive CT monitoring, measured value processing, and trip circuit supervision ، Optional features: 1/3-pole or 3-pole CB failure protection, end-fault protection, external trip signals, phase/ground overcurrent protection, cross-stabilization, bus coupler differential protection ، Integrated DIGSI 5 and modular hardware/software