Siemens Argus 7SR21 - Page 541

7SR210 & 7SR220 Commissioning & Maintenance Guide
© 2013 Siemens Protection Devices Limited Page 29 of 82
P.U.
D.O.
&
TIMING
TESTS
Ph. Dir
Char.
(NI EI VI LTI,
DTL)
Is
(A)
TM
Operate C
urrent
Operate Time
P.U.
(Amps)
D.O.
(Amps)
Tol
2 x Is
(sec)
5 x Is
(sec)
Tol
E
Calculated Timing values in seconds for TM =1.0
Curve 2 xIs 5 xIs
IEC-NI 10.03 4.28
IEC-VI 13.50 3.38
IEC-EI 26.67 3.33
IEC-LTI 120.00 30.00
ANSI-MI 3.80 1.69
ANSI-VI 7.03 1.31
ANSI-EI 9.52 1.30
Note that the operate time may be subject to the Minimum op time setting for the element and/or may have a
Follower DTL applied.
1.1.1.1 Element Blocking
The Derived Earth Fault elements can be blocked by Binary Input Inhibit, VT Supervision and Inrush Detector
operation. The Characteristic can be made non-directional by VT Supervision. This functionality should be
checked.
Element BI Inhibits VTS action Inrush Detector
51N-1
51N-2
51N-3
51N-4
50N-1
50N-2
50N-3
50N-4