Siemens 7SJ85 - Page 424

Parameter: Min. time of the curve
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Default setting (_:8161:114) Min. time of the curve = 0.00 s
This parameter is only available in the advanced stage.
With the parameter Min. time of the curve, you define a minimum operate delay time. The operate
delay time of inverse-time characteristic curve never falls below the minimum operate delay time. If the
setting is left on its default value of 0 s, this parameter has no effect on the inverse-time characteristic curve.
This parameter is only required for time coordination in recloser schemes. For all other applications, Siemens
recommends keeping the default setting of 0 s.
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i
NOTE
If the set value is smaller than the smallest possible time delay of the inverse-time characteristic curve, the
parameter has no influence on the delay time.
Parameter:
Additional time delay
•
Default setting (_:8161:115) Additional time delay = 0.00 s
With the parameter Additional time delay, you define a definite-time delay in addition to the inverse-
time delay.
If the setting is left on its default value of 0 s, this parameter has no effect on the inverse-time characteristic
curve.
This parameter is only required for time coordination in recloser schemes. For all other applications, Siemens
recommends keeping the default setting of 0 s.
Parameter: Threshold
•
Default setting (_:8161:3) Threshold = 1.50 A
The same considerations apply to setting the threshold value as for non-directional overcurrent protection.
Therefore, refer to chapter 6.3.5.2 Application and Setting Notes for further information.
Parameter: Time dial
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Default setting (_:8161:101) Time dial = 1
Use the Time dial parameter to displace the characteristic curve in the time direction.
The set value for the Time dial parameter is derived from the time-grading chart that has been prepared for
the electrical power system.
Where no time grading and therefore no displacement of the characteristic curve is required, leave the Time
dial parameter at 1 (default setting).
Parameter: Reset
•
Default setting (_:8161:131) Reset = disk emulation
You use the Reset parameter to define whether the stage drops out according to the dropout characteristic
curve (in accordance with the behavior of a disk emulation = rotor disk) or instantaneously.
Parameter Value
Description
disk emulation
Select this setting if the device is coordinated with electromechanical
devices or other devices which perform a dropout after a disk emulation.
instantaneous
Use this setting if the dropout is not to be performed after disk emulation
and an instantaneous dropout is desired instead.
Protection and Automation Functions
6.6 Directional Overcurrent Protection, Phases
424 SIPROTEC 5, Overcurrent Protection, Manual
C53000-G5040-C017-8, Edition 07.2017