Characteristics - Siemens siprotec 7SD5 User Manual

1.3

Characteristics

General Features • Powerful 32-bit microprocessor system
• Complete digital processing of measured values and control, from the sampling of
• Complete galvanic and reliable separation between internal processing circuits
• Suited for lines with up to 6 ends, even with transformers in the protected zone
• Simple device operation using the integrated operator panel or a connected person-
• Storage of fault indications as well as instantaneous values for fault recording
Differential • Differential protection system for up to 6 ends with digital protection data transmis-
Protection
• Protection for all types of short-circuits in systems with any starpoint conditioning
• Reliable distinction between load and short-circuit conditions, also on high resistant
• High sensitivity in the case of a weakly loaded system, extreme stability against
• Due to phase segregated measurement the pickup sensitivity is independent of the
• Suited for transformers in the protected area (order option)
• Detection of high-resistant, weak-current faults due to high sensitivity;
• Insensitive against in-rush and charge currents — also for transformers in the pro-
• Charging current compensation; therefore increased pickup sensitivity
• High stability also for different current transformer saturation
• Adaptive restraint that is automatically derived from the measured values and the
• Fast phase segregated tripping also on weak or zero infeed ends (breaker intertrip)
• Low dependence on frequency due to frequency tracking
• Digital transmission of protection data; communication between devices via dedi-
• Communication possible via ISDN networks or pilot wire connections (up to 30 km,
• Permanent supervision of the protection data transmission concerning disturbance,
• Automatic changeover of communication paths in case of transmission failure or
7SD5 Manual
C53000-G1176-C169-1
the analog input values, the processing and organization of the communication
between devices up to the closing and tripping commands to the circuit breakers
from the measurement, control, and power supply circuits by analog input transduc-
ers, binary inputs and outputs and the DC/DC or AC/DC converters
(order option)
al computer with operator guidance
sion
faults with small fault currents;
load jumps and power swings
type of fault
tected area — and against higher-frequency switching transients;
configured current transformer data
cated communication connections (in general optical fibre) or a communication
system
depends on the type of pilot wire);
failure, and transfer time deviation in the transmission network, with automatic
transfer time correction
transmission disturbance is provided (for ring topology with 7SD5*3)
1.3 Characteristics
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