7SR210 & 7SR220 Description of Operation
Unrestricted ©2018 Siemens Protection Devices Limited
Page 39 of 94
Figure 3.5.1-1 Logic Diagram: SEF Directional Element (67SEF)
3.5.2
Instantaneous Sensitive Earth Fault Protection (50SEF)
Two instantaneous SEF elements are provided in the 7SR21 relay. Four elements are provided in the 7SR22
relay e.g. giving the option of using two elements set to forward and two to reverse.
Each instantaneous element has independent settings for pick-up current
50SEF-n Setting
and a follower time
delay
50SEF-n Delay
. The instantaneous elements have transient free operation.
Where directional elements are present the direction of operation can be set using
50SEF-n Dir. Control
setting.
Directional logic is provided independently for each 50SEF-n element.
Operation of the instantaneous earth fault elements can be inhibited from: -
Inhibit 50SEF-n
A binary or virtual input, function key or remote data Comms
79 SEF Inst Trips:
50SEF-n
When ‘delayed’ trips only are allowed in the auto-reclose sequence
(
79 SEF Prot’n Trip n
=
Delayed
).
50SEF-n VTSAction:
Inhibit
Operation of the VT Supervision function (7SR22).
Directional elements will not operate unless the zero sequence voltage (V
0
) is above the
67SEF Minimum
Voltage
setting i.e. the residual voltage is greater than 3 times this setting and the phase is in the
Forward/Reverse operating range. If
67SEF Wattmetric
is set to Enabled, the calculated residual real power
must be above the
67SEF Wattmetric Power
setting for any SEF element operation. The residual power P
res
is
equal to the wattmetric component of 3V
0
I
SEF
and therefore the wattmetric component of 9V
0
I
0
Summary of Contents for Argus 7SR21
Page 1: ...Energy Management 7SR21 7SR22 Argus Overcurrent Relay Reyrolle Protection Devices ...
Page 2: ......
Page 4: ...Contents 7SR11 and 7SR12 Page 2 of 2 2018 Siemens Protection Devices Limited ...
Page 185: ...7SR210 Settings Guide Unrestricted 2018 Siemens Protection Devices Limited Page 61 of 61 ...
Page 277: ...7SR220 Settings Guide Unrestricted Page 72 of 107 2013 Siemens Protection Devices Limited ...
Page 382: ...7SR220 Technical Manual Chapter 4 Page 2 of 96 2017 Siemens Protection Devices Limited ...
Page 386: ...7SR220 Technical Manual Chapter 4 Page 6 of 96 2017 Siemens Protection Devices Limited ...
Page 398: ...7SR220 Technical Manual Chapter 4 Page 18 of 96 2017 Siemens Protection Devices Limited ...
Page 414: ...7SR220 Technical Manual Chapter 4 Page 34 of 96 2017 Siemens Protection Devices Limited ...
Page 466: ...7SR220 Technical Manual Chapter 4 Page 86 of 96 2017 Siemens Protection Devices Limited ...
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Page 470: ...7SR220 Technical Manual Chapter 4 Page 90 of 96 2017 Siemens Protection Devices Limited ...
Page 472: ...7SR220 Technical Manual Chapter 4 Page 92 of 96 2017 Siemens Protection Devices Limited ...
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