Siemens 6MD85, Manual

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The parameter
CT connection
shows the connection type of the current transformer for the 3-phase
current measuring point. The parameter can be found in the DIGSI 5 project tree under Name of the device
→ Parameter → Power system → Measuring point I 3-phase. You cannot change the connection type of
the current transformer in the Power system.
You can change the connection type of the current transformer only under measuring point routing in DIGSI 5.
Under Name of the device → Measuring point routing → Current measuring points, select the desired
connection type under Connection type. The following types of connections are possible:
•
3-phase + IN-separate
•
3-phase + IN
•
3-phase
•
3-phase, 2 primary CT
•
3ph,2prim.CT + IN-sep
•
2ph, 2p. CT + IN-sep
Depending on the connection type selected, you must route the measured values to the terminals of the
current measuring point in DIGSI 5. You can find connection examples for current transformers in chapter
A.
6 Connection Examples for Current Transformers . The connection examples provide assistance when selecting
the type of connection.
Parameter: Tracking
•
Default setting
(_:8881:127) Tracking
=
active
With the parameter
Tracking
, you specify whether you would like to work with the sampling-frequency
tracking function.
Parameter Value Description
active
If the parameter
Tracking
=
active
has been set, the measuring point
will be included when determining the sampling frequency. If possible, only
the 3-phase measuring points shall be considered.
Siemens recommends using the default setting.
Note: If the parameter
Tracking
=
active
, the determined sampling
frequency applies to all functions in the device not using fixed sampling
rates.
inactive
If the channels of the measuring point are not to be considered for deter-
mining the sampling frequency, please select the setting value
inactive
.
Parameter: Rated primary current
•
Default setting
(_:8881:101) Rated primary current
=
1000 A
With the
Rated primary current
parameter, the active rated primary current of the current transformer
is set.
Parameter: Rated secondary current
•
Default setting
(_:8881:102) Rated secondary current
=
1 A
With the
Rated secondary current
parameter, you set the current rated secondary current of the current
transformer.
Parameter: Current range
•
Default setting
(_:8881:117) Current range
=
100 x IR
The
Current range
parameter allows you to set the dynamic range for the current input. Please retain the
default setting for power-system protection applications. The current measuring range 1.6 x Irated applies for
the connection type
3-phase + IN-separate
and the sensitive current input or for the measuring inputs.
Function-Group Types
5.1 Power-System Data
SIPROTEC 5, High-Voltage Bay Controller, Manual 187
C53000-G5040-C015-9, Edition 11.2017