Siemens 6MD85, Manual

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There are consistency checks that validate the connections of voltage measuring points to the function group:
•
The connection type must be identical for all measuring points connected to the same interface.
•
It is not permitted to route a measuring point to the function group using the option VN.
•
The rated voltage (primary and secondary) must be identical for all measuring points connected to the
same interface.
•
If more than 1 measuring point is connected to 1 voltage interface, a function block must be expanded to
enable selection of the synchronization voltage.
CFC Control
The voltages are selected by CFC logic on the basis of the measuring point IDs. If more than one measuring
point is connected to interfaces V
sync1
or V
sync2
of the Circuit-breaker function group, the
V sync select.
function block has to be removed from the library in the Circuit-breaker function group. A CFC logic (see
following example) has to define IDs for the
V sync1
or
V sync2
inputs of this function block in order to
ensure the correct measuring point connection for the Synchrocheck function.
[scdynmsx-160212-01.tif, 1, en_US]
Figure 6-69 CFC Logic: Voltage Selection Using Measuring Point ID
If no measuring point can be selected because of the switch or disconnector positions, the ID0 is used. If ID0 is
selected, the indication
(_:2311:304) Blocked no V selected
is set. The synchrocheck is blocked. If
you have activated the parameter
(_:5071:108) Direct close command
, unsynchronized switching is
still possible.
Control Functions
6.4 Synchronization Function
374 SIPROTEC 5, High-Voltage Bay Controller, Manual
C53000-G5040-C015-9, Edition 11.2017