7SR210 & 7SR220 Description of Operation
Unrestricted ©2018 Siemens Protection Devices Limited
Page 33 of 94
50N-n
>
c
50N-n
Setting
If directional elements are not present this block is
omitted and the '50N-n Dir En' signal is set TRUE.
Forward
Reverse
50N-n Dir
Non-Dir
1
&
&
50N-n Dir En
67N Fwd
67N Rev
50N-n Delay
50N-n VTS Action
Off
Non Dir
Inhibit
VT Fail
&
&
&
1
IL1
IL2
IL3
I
N
Inhibit 50N-n
50N-n Element
Enabled
Disabled
81HBL2
50N-n Inrush
Action
Off
Inhibit
&
50N-n Dir En
General Pickup
&
79 P/F Inst Trips
= 50N-n
79 P/F Prot’n Trip n
= Delayed
AUTORECLOSE
Inhibit 50N-n
General Pickup
50N-n
&
Figure 3.3.2-1
Logic Diagram: Derived Instantaneous Earth Fault Element
3.3.3
Time Delayed Derived Earth Fault Protection (51N)
Two time-delayed derived earth fault 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.
51N-n Setting
sets the pick-up current level.
A number of shaped characteristics are provided. An inverse definite minimum time (IDMT) characteristic is
selected from IEC and ANSI curves using
51N-n Char
. A time multiplier is applied to the characteristic curves
using the
51N-n Time Mult
setting. Alternatively, a definite time lag delay (DTL) can be chosen using
51N-n
Char
. When Delay (DTL) is selected the time multiplier is not applied and the
51N-n Delay (DTL)
setting is used
instead.
The
51N-n Reset
setting can apply a
definite time delayed
reset
,
or when configured as an ANSI characteristic
an
ANSI (DECAYING)
reset. If ANSI (DECAYING) reset is selected for an IEC characteristic, the reset will be
instantaneous. The reset mode is significant where the characteristic has reset before issuing a trip output – see
‘Applications Guide’.
A minimum operate time for the characteristic can be set using the
51N-n Min. Operate Time
setting.
A fixed additional operate time can be added to the characteristic using the
51N-n Follower DTL
setting.
Where directional elements are present the direction of operation can be set using
51N-n Dir. Control
setting.
Directional logic is provided independently for each 51N-n element.
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 ...
Page 468: ...7SR220 Technical Manual Chapter 4 Page 88 of 96 2017 Siemens Protection Devices Limited ...
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 ...
Page 643: ...Unrestricted ...