Siemens 6MD85, Manual

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The function group has interfaces with
•
Measuring points
•
Circuit-breaker function group
Interface with Measuring Points
The function group receives the required measured values via its interfaces with the measuring points. If you
are using an application template, the function group is already connected to the necessary measuring points.
If you add functions to the function group, they will automatically receive the measured values from the
correct measuring points. If you add protection functions to the function group but the necessary measuring
point is not connected, DIGSI 5 reports an inconsistency. Configure the measuring points in DIGSI 5 via the
Function group connections editor. You can find more detailed information in chapter
2 Basic Structure of
the Function .
The function group has the following interfaces with the measuring points:
•
3-phase current
The measurands from the 3-phase power system are supplied via this interface. Depending on the
connection type of the transformers, these are, for example, I
A
, I
B
, I
C
, I
N
or 3I
0
. All values that can be
calculated from the measurands are also provided via this interface. The function group must always be
connected to the I-3ph measuring point.
You can connect the 3-phase current interface to a maximum of four 3-phase current measuring points
(for example, for 1 1/2 circuit-breaker layouts). If 2 current measuring points have been connected with
the 3-phase current interface, the total current is also determined from measured values from both
measuring points in the function group. All functions in the function group have access to these values.
•
3-phase voltage (optional)
The measurands from the 3-phase voltage system are supplied via this interface. There are various types
of transformer connections possible. All values that can be calculated from the measurands are also
provided via this interface. Connecting the function group to the V 3ph measuring point is optional.
You can connect multiple measuring points with this interface. You can find more information in chapter
5.9 Voltage Measuring-Point Selection .
If you want to test or change the connection between the voltages and the V-3ph measuring point,
double-click in the DIGSI 5 project tree → (Name of the device) on Measuring point routing (Connec-
tion type = 3 phase-to-ground voltage). For more information, refer to the description of the power-
system data starting in chapter
5.1 Power-System Data .
Interface to the Circuit-Breaker Function Group
All required data is exchanged between the Voltage-current 3-phase function group and the Circuit-breaker
function group via the interface of the Circuit-breaker function group.
This data includes, for example, the pickup and operate indications of the protection functions sent in the
direction of the Circuit-breaker function group and, for example, the circuit-breaker condition information in
the direction of the protection function groups.
The Voltage-current 3-phase function group is connected to one or more Circuit-breaker function groups.
This connection generally determines:
•
Which circuit breaker(s) is/are activated by the protection functions of the protection function group
•
Starting the Circuit-breaker failure protection function (if available in the Circuit-breaker function group)
through the protection functions of the connected protection function group
•
Starting the Automatic reclosing function (AREC, if available in the Circuit-breaker function group)
through the protection functions of the connected Protection function group
Besides the general allocation of the protection function group to the Circuit-breaker function groups, you can
also configure the interface for certain functionalities in detail. Configure the details in DIGSI 5 using the
Circuit-breaker interaction editor in the protection function group.
Function-Group Types
5.2 Function-Group Type Voltage/current 3-Phase
194 SIPROTEC 5, High-Voltage Bay Controller, Manual
C53000-G5040-C015-9, Edition 11.2017