Triple Single Mode; Overview; Setting Notes - Siemens 7SC80 Manual

2.16

Triple Single Mode

The 3-/1-pole operation function allows opening and closing each single phase individually in systems in
which the three phases are used independently of one another. Thus, interruptions on the other, unfaulted
phases are reduced. This function allows asynchronous reclosing cycles in the three phases with one single
controller at the point of infeed. The protection functions time overcurrent protection and directional time
overcurrent protection supply information about the faulty phases. The 3-/1-pole mode of operation is not
effective if the automatic reclosing function (AR) is inactive.
If the AR function is deactivated, the TRIP commands of the protection function are always 3-pole, regardless
of the selected mode.

Overview

2.16.1
The Triple/Single function has three operating modes which can be changed via an operator panel, DIGSI,
or a switchable parameter group. Thus, the operating mode can be adapted to the system requirements.
The three different operating modes are selected with the help of parameter 7400 Triple/Single:
•
In 3PTrip-3PLO mode, only 3-pole trippings and 3-pole reclosures are possible. The final TRIP of the AR
function applies to all 3 phases. In this mode, the 7SC80 works like a 3-pole device.
•
The 1PTrip-3PLO mode allows 1-pole TRIP commands by the protection function for faults that affect
only one phase and are parameterized as AR initiation function. For multi-pole faults that are detected by
these protection functions, 3-pole tripping and 3-pole reclosure is performed. In the case of a simulta-
neous 3-pole fault, a 1-pole reclosing sequence is converted into a 3-pole reclosure or final TRIP. If the 1-
pole reclosing cycles have not been successful, a 3-pole final TRIP is performed.
•
The 1PTrip-1PLO mode allows operating the 3 poles independently of one another for fault clearing,
provided that only one single phase is affected. Final TRIP of the AR is performed phase-wise. In this
mode, final TRIP indications can be issued phase-wise and independently of one another. This can be
done either by a protection function that was not parameterized as initiation function or after unsuc-
cessful reclosing cycles of the initiating protection function. The 1- or 2-pole final TRIP does not affect
subsequent reclosing cycles of the other phases. If triggered by the time overcurrent protection ground
or sensitive ground fault protection, a 3-pole TRIP is only carried out if no phase-to-ground fault exists. In
this case, 1-pole tripping is initiated.
•
If 1PTrip-3PLO or 1PTrip-1PLO is selected as operating mode and 1 or 2 phase(s) is/are open, the
ground fault protection functions are blocked dynamically and the functions negative sequence protec-
tion, overvoltage protection, current and voltage monitoring are blocked.
Moreover, for these operating modes, the synchrocheck function cannot be used in combination with the
AR function. With the indications 6020
reclosing cycle of the phase changes to the final TRIP state. They are only used in the operating modes
1PTrip-3PLO and 1PTrip-1PLO. Operating mode 1PTrip-3PLO: If the indication is active, the next
reclosing cycle causes a 3-pole final TRIP. Operating mode 1PTrip-1PLO: If the indication is active, the
next reclosing cycle causes a 1-pole final TRIP of the respective phase. The other phases will not be
affected by this.

Setting Notes

2.16.2
The 3-/1-pole operating mode is only effective and accessible if address 374 Triple Single is set to
Enabled. If this function is not required, Disabled is set.
You can specify the mode at the address 7400 Triple/Single.
Mode 3 Phase Trip, 3 Phase Lockout
This mode allows the 7SC80 to work as a normal 3-pole reclosing device. The TRIP information of the protec-
tion functions is simultaneously output to all 3 poles. The automatic reclosing (AR) CLOSE commands are 3-
pole, too.
SIPROTEC Compact, 7SC80, Manual
E50417-G1140-C486-A8, Edition 07.2017
>79 Lockout Ph1 to 6022 >79 Lockout Ph3 , the next
Functions
2.16 Triple Single Mode
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