2.1 General
33
7ST6 Manual
E50417-G1176-C251-A3
2.1.3
Power System Data 1
The device requires certain basic data regarding the protected equipment, so that the
device will be compatible with its desired application. This comprises e.g. nominal
system data, nominal data of transformers, polarity ratios and their physical connec-
tions, in certain cases circuit breaker properties, and similar. Furthermore, there are
a number of settings associated with all functions rather than a specific protection,
control or monitoring function. These data can normally only be changed from a PC
running DIGSI
®
and are discussed in this subsection.
2.1.3.1
Setting Notes
General
In DIGSI
®
double-click on
Settings
to display the relevant selection. A dialog box with
the tabs General, Transformer data, System data, Voltage transformers and Circuit
breaker will open under
Power System Data 1
, in which you can configure the in-
dividual parameters. Thus, the following subsections are structured accordingly.
At address
245
BI CONTROL
you specify the control of the binary inputs for the
zone/catenary changeover (
Edge
/
Level
).
Transformer Data
In address
201
CT Starpoint
the polarity of the current transformers must be
stated. This setting determines the measuring direction of the device (forwards = line
direction).
The measured value connections can be found in the Appendix under A.3.
At address
202
CT PRIMARY
you set the primary rated CT current (overhead contact
line current). The secondary rated current is set in address
203
CT SECONDARY
.
At addresses
204
Unom PRIMARY
and
205
Unom SECONDARY
, information is entered
regarding the primary and secondary current ratings of the current transformers.
It is important to ensure that the rated secondary current of the current transformer
matches the rated current of the device, otherwise the device will incorrectly calculate
primary data.
Correct entry of the primary data is a prerequisite for the correct computation of oper-
ational measured values with primary magnitude. If the settings of the device are per-
formed with primary values using DIGSI
®
, these primary data are an indispensable re-
quirement for the fault-free operation of the device.
Transformer Data
for Auto-transform-
er Systems
At address
206
IF CT STARPOINT
the polarity of the current transformers (negative
feeder current) must be stated. This setting determines the measuring direction of the
device (forwards = line direction).
The measured value connections can be found in the Appendix under A.3.
At address
207
IF CT PRIMARY
you set the primary rated CT current (negative
feeder current).
At addresses
209
UF PRIMARY
and
210
UF SECONDARY
, information regarding the
primary and secondary current ratings of the current transformers (negative feeder
voltage) is entered.
Please heed the detailed description given in chapter 2.21!
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