Siemens Siprotec 7VK61 Manual page 22

Introduction
1.3 Characteristics
Monitoring Functions
• Availability of the device is greatly increased because of self-monitoring of the internal measurement circuits,
power supply, hardware and software
• Monitoring of the current and voltage transformer secondary circuits by means of summation and symmetry
checks
• Trip circuit supervision
• Checking for the measured direction and the phase sequence.
Additional Functions
• Battery buffered real time clock, which may be synchronized via a synchronization signal (e.g. DCF77, IRIG
B via satellite receiver), binary input or system interface
• Continuous calculation and display of measured quantities on the front display;
• Fault event memory (trip log) for the last 8 network faults (faults in the power system), with real time stamps;
• Fault recording and data transfer for fault recording for a maximum time range of 15 s;
• Statistics: Counter with the trip commands issued by the device, as well as recording of the fault current data
and accumulation of the interrupted fault currents;
• Communication with central control and memory components possible via serial interfaces (depending on
the individual ordering variant), optionally via data line, modem or fibre optics;
• Commissioning aids such as connection checks as well as circuit breaker test functions.
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SIPROTEC, 7VK61, Manual
C53000-G1176-C159-3, Release date 05.2009