Introduction
1.1 Overall Operation
SIPROTEC, 7SC805, Manual
C53000-G1140-C380-1, Release date 05.2014
14
1.1
Overall Operation
The SIEMENS device 7SC805 is a stand-alone merging unit with KEMA-certified to the standard IEC 61850-
9-2 process bus. MU 7SC805 digitizes the output of conventional instrument transformers synchronous to a
time synchronization signal and then converts them to sampled measured value telegrams according to IEC
61850-9-2 standard. In addition, the 7SC805 supports data exchange via GOOSE telegrams with KEMA-cer-
tificated according to IEC 61850 and primary equipment control command functions via GOOSE.
The MU device 7SC805 complements the SIPROTEC 5 relays with an IEC 61850-9-2 interfaces for building
digital bays or full digital substations.
Analog Inputs
The measuring inputs (MI) convert the currents and voltages which come from the instrument transformers and
adapt them to the level appropriate for the internal processing of the device.
The merging unit device features the following connections:
• 4 conventional current transformers
• 4 conventional voltage transformers
Figure 1-1
Hardware structure of Merging Unit 7SC805