Application And Setting Notes - Siemens 6MD85 Manual

Function-Group Types
5.6 Function-Group Type Circuit Breaker, 1-/3-Pole
•
with I< & aux.contact
With the criteria with I< and with I< & aux.contact, the condition of the circuit breaker is also
taken into account as a further criterion in addition to the dropout of the tripping function (operate indi-
cation is terminated by command). You can select whether the state is determined by means of the
current (with I<) or by means of the current in conjunction with the circuit-breaker auxiliary contacts
(with I< & aux.contact). The behavior of these setting options only differs in one situation of the
circuit-breaker condition. If the circuit breaker is in the opening condition, the trip command is reset in
the case of the option with I<, whereas it is not reset yet in the case of the option with with I< &
aux.contact. The opening condition is detected when the auxiliary contacts still detect the circuit
breaker as being closed and opening is detected via the decreasing current flow.
As long as the circuit breaker is detected unambiguously as closed (fully closed), the trip command will
not be reset with these setting options.
The information about the condition of the circuit breaker is supplied by the Circuit-breaker position
recognition function block (see
described in this chapter.
5.6.4.2

Application and Setting Notes

Parameter: 1-pole tripping permitted
For this, see 5.6.3 Application and Setting Notes
Parameter: 3-Pole Coupling
•
Default setting (_:5341:102) 3-pole coupling = with trip
Parameter Value
with trip
with pickup
EXAMPLE
If 2 1-phase ground faults occur on different lines - for example, including parallel lines - (see
protection devices will detect fault types A-B-E at all 4 line ends, that is, with a pickup characteristic corre-
sponding to a 2-phase ground fault. However, since there is only one 1-phase short circuit on each of the 2
lines, it is desirable to have a short 1-pole interruption on each of these 2 lines. This is possible with a setting
with trip command. Each of the 4 devices detects an internal 1-phase short circuit and can therefore cause 1-
pole tripping.
[dwfehler-030211-01.tif, 1, en_US]
Figure 5-36
234
5.6.6.1
Description
With this setting, every multipole trip command results in 3-pole tripping. If a 1-
phase short circuit is present within the tripping zone and any other fault is
present outside the zone, 1-pole tripping is possible.
Even an additional fault during 1-pole tripping also results in 3-pole coupling
only if it occurs within the tripping zone.
With this setting every multiphase pickup results in a 3-pole trip, even if only
one 1-phase ground fault is present in the tripping zone and one further fault is
detected, for example due to overcurrent.
Even if a 1-pole trip command is pending, any further pickup will result in a 3-
pole coupling.
Multiphase Short Circuit on a Double Line
Overview). The determination of the various conditions is also
.
SIPROTEC 5, High-Voltage Bay Controller, Manual
Figure 5-36), the
C53000-G5040-C015-9, Edition 11.2017