Siemens 6MD85, Manual

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•
Parameter:
Sensor
=
point sensor
•
Parameter:
External trip initiation
=
no
Stage 3 (cable-connection compartment supervision):
•
Parameter:
Operate & flt.rec. blocked
=
yes
If an arc is detected in the cable-connection compartment of the infeed (light-gray point sensors in
Figure 7-201 ), a pickup indication is generated immediately. The arc is switched off by a superordinate
protection device.
Depending where the arc is generated in the cable-connection compartment of the infeed, it is not
always possible to measure the current. If an arc is detected in the cable-connection compartment of the
infeed, the current must be evaluated by the superordinate protection device.
•
Parameter:
Channel
=
•
Parameter:
Operating mode
=
light only
•
Parameter:
Sensor
=
point sensor
•
Parameter:
External trip initiation
=
no
Stage 4 to 7 (External trip initiation):
•
Parameter:
Operate & flt.rec. blocked
=
no
•
Parameter:
Operating mode
=
current and light
•
Parameter:
External trip initiation
=
light
If an arc is detected in the busbar compartment or the circuit-breaker compartment of the feeder, the
feeder device sends the
Light detected
indication to the infeed device. Only if the indication in the
infeed device
Light detected
is connected with the signal
>External light
, an external trip
initiation via these stages is effective.
The protection device in the infeed evaluates the current. If the measured current exceeds the
Threshold I>
and/or
Threshold 3I0>
threshold values, the protection device in the infeed switches
off the arc.
Application and Setting Notes for Variant 2 (with Feedback to Feeder Protection Devices)
General Notes:
•
Connect the optical sensors in the busbar compartment, the CB compartment, and the cable-connection
compartment of the feeder 1 and 2 and the infeed to the respective protection devices.
•
Arcs in the busbar compartment and in the CB compartment of the feeders must be cleared by the
protection device in the infeed. To do this, the protection devices in the feeder must send the indication
Arc detected
to the infeed device. Use the binary inputs/outputs, a protection interface, or IEC 61850
GOOSE.
•
Arcs in the cable-connection compartment of the feeder are cleared selectively. Here, the message
Arc
detected
is sent as well via binary inputs/outputs, a protection interface, or IEC 61850 GOOSE to the
protection device in the infeed.
The protection device in the infeed evaluates the current. If the measured current exceeds the threshold
values
Threshold I>
and/or
Threshold 3I0>
, the protection device in the infeed sends the pickup
indication of the stage back to the protection device in the affected feeder. The protection device in the
affected feeder clears the arc selectively.
Due to the pressure wave that occurs during an arc, partitions may deform and cause undesirable light
influences in adjacent compartments. This may result in a non-selective trip.
i
i
NOTE
The External trip initiation function must be instantiated in the protection devices of the feeders.
7.29.10.3
Protection and Automation Functions
7.29 Arc Protection
928 SIPROTEC 5, High-Voltage Bay Controller, Manual
C53000-G5040-C015-9, Edition 11.2017