Setting Notes - Siemens 7SC80 Manual

2.1.3.2

Setting Notes

General
In DIGSI, double-click Settings to open the corresponding dialog box. In doing so, a dialog box with tabs
opens under P.System Data 1, in which individual parameters can be configured. The following descrip-
tions are therefore structured according to these tabs.
Rated Frequency (Power System)
The rated system frequency is set at address 214 Rated Frequency. The factory setting of the model
number must only be changed if the device is to be used for a different purpose than intended when ordering.
In US device versions (MLFB position 10 = C), parameter 214 is preset to 60 Hz.
Phase Rotation (Power System)
Address 209 PHASE SEQ. is used to change the default phase sequence (A B C for clockwise rotation) if
your power system permanently has an anti-clockwise phase sequence (A C B. A temporary reversal of rota-
tion is also possible using binary inputs (see Section
Phase Rotation (Power System)
At address 201 CT Starpoint, you enter the polarity of the current transformers, that is, the location of the
CT neutral point (the following figure applies correspondingly for two current transformers). This setting
determines the measuring direction of the device (forward = line direction). The reversal of this parameter
also reverses the polarity of the ground current inputs Ι
[polung-stromwandler-020313-kn, 1, en_US]
Figure 2-4
Current Connection Ι4 (Power System)
Here, it is communicated to the device whether the ground current of the current transformer neutral point is
connected to the fourth current input (Ι
example in C Connection
cases, even if the ground current of the own line is measured via a separate ground current transformer, enter
the setting NO. This setting exclusively affects the function "Current Sum Monitoring" (see Section
2.12.1 Measurement
Voltage Connection (Power System)
Address 213 specifies how the voltage transformers are connected.
VT Connect. 3ph = Van, Vbn, Vcn means that the three phase voltages are wye connected, i.e. the
three phase-to-ground voltages are measured.
SIPROTEC Compact, 7SC80, Manual
E50417-G1140-C486-A8, Edition 07.2017
Polarity of current transformers
). This corresponds to the Holmgreen connection, (see connection
4
Examples). In this case, parameter 280 Holmgr. for Σi is set to YES. In all other
Supervision).
2.24.2 Setting Notes).
.
N
Functions
2.1 General
49