Siemens 6MD85, Manual

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Transformer Tap Changers
Function Description
With the device control function, you can change a transformer tap by moving it higher or lower and monitor
the proper execution of the adjusting commands.
The function has built-in comprehensive options for measuring the tap changer position as well as supervision
functions. The supervision functions are used to check the voltage and supply information about the tap posi-
tion for adaptive matching of the transformer differential protection.
The following options are provided for control:
•
Direct user commands via the device keypad or routed binary inputs
•
User-defined conditions via the CFC
If the tap changer reaches the end positions, the control function issues the
(_:301) End higher
pos.reached
or
(_:302) End lower pos.reached
indication.
The transformer tap controller is controlled by the function group Tap changer, which you can select from the
DIGSI library (group Switching devices).
[sc_tssdig, 1, en_US]
Figure 6-108 Tap Changer Functionality in the DIGSI Information Matrix
The central element is the Controllable Position of type BSC (Binary Controlled Step Position Information,
based on IEC 61850). You connect this Controllable in the matrix to the desired number of binary inputs that
indicate the current tap position.
You can find more information in chapter
6.8.2 Application and Setting Notes .
The Position Controllable also contains parameters. If you wish to change the settings, you must select the
Controllable in the DIGSI information matrix and change the settings by way of the Properties dialog. The taps
are controlled via the commands Higher command and Lower command, each of which must be connected
to one binary output.
6.8
6.8.1
Control Functions
6.8 Transformer Tap Changers
SIPROTEC 5, High-Voltage Bay Controller, Manual 437
C53000-G5040-C015-9, Edition 11.2017