General Notes For Setting The Threshold Value Of Trigger Functions; Overview; Modifying The Transformer Ratios In Digsi 5 - Siemens SIPROTEC 5 Manual

3.7

General Notes for Setting the Threshold Value of Trigger Functions

Overview

3.7.1
You can set the threshold values of trigger functions directly on the device or by using DIGSI 5.
An innovative design was implemented for the settings.
You can switchover the edit mode between the following setting views:
•
Primary
•
Secondary
•
Percent
If you change settings in a setting view, DIGSI 5 calculates the settings of the 2 inactive views in the back-
ground. If you wish to save, for example, conversion to secondary values, then select the primary view.
Configure all the settings and switchover to the secondary view.
Edit Mode: Primary
The parameters are set as primary values and thus refer directly to the primary system. The manual conversion
on the secondary circuit omitted.
Edit Mode: Secondary
The settings refer to the secondary circuit of the transformer. This means that the settings must be converted.
Edit Mode: Percent
The setting values can be standardized. The reference values for the percentage setting are always the
nominal variables (phase-to-phase variables) of the function groups such as FG 3-phase voltage or FG 3-
phase current / voltage. The setting values are, thus, related exclusively to the primary settings.
NOTE
i i
If other reference values are used, then this is documented for the respective function in the chapter Appli-
cation and Setting Notes.
Recommendation for Setting Sequence
When setting the trigger functions, Siemens recommends the following procedure:
•
First set the transformation ratios of the transformers. You can find these under Power-system data.
•
In addition, set the reference parameters for the percent setting. These parameters are located, for
example, in the function group 3-phase voltage/current in the General function block. .
•
Next, set the parameter of the trigger functions.
If the transformer data have changed after completing the setting, remain in the setting sheet (for
example, primary setting) and change the transformer data. In the background, DIGSI 5 obtains the new
settings in the inactive setting views (for example, new secondary values).
The following section explains, by way of an example, how to modify the transformer ratios in DIGSI 5 using
the corresponding alternatives.

Modifying the Transformer Ratios in DIGSI 5

3.7.2
Threshold-Value Setting in an Example of the Voltage Transformer
In the Default Setting, DIGSI is Set to the Secondary Edit Mode.
SIPROTEC 5, Fault Recorder, Manual
C53000-G5040-C018-5, Edition 11.2017
3.7 General Notes for Setting the Threshold Value of Trigger Functions
System Functions
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