Siemens 7SJ82 - Application Example for Arc Protection with a Line Sensor in Operating Mode: Light and Current; Description

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Parameter: Sensor = point sensor
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Parameter: External trip initiation = no
Stage 3 (cable-connection compartment supervision):
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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 6-94), 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.
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Parameter: Channel =
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Parameter: Operating mode = light only
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Parameter: Sensor = point sensor
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Parameter: External trip initiation = no
Stage 4 to 7 (External trip initiation):
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Parameter: Operate & flt.rec. blocked = no
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Parameter: Operating mode = current and light
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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 Example for Arc Protection with a Line Sensor in Operating Mode:
Light and Current
Description
Overview
The example describes the Arc protection function in a medium-voltage switchgear with 1 infeed and
2 feeders. The Arc protection function operates with the Operating mode = current and light. In the
example, all arcs are detected by the protection device in the infeed.
The following items are considered in the example below:
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Optical line sensor placement in the switchgear
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Optical line sensor connection to the protection device in the infeed
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Number of necessary stages of the functions in the infeed protection device
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Setting notes about the selected parameters in the stages of the function
6.10.11
6.10.11.1
Protection and Automation Functions
6.10 Arc Protection
516 SIPROTEC 5, Overcurrent Protection, Manual
C53000-G5040-C017-8, Edition 07.2017