7PG2113/4/5/6 Commissioning & Maintenance
©2012 Siemens Protection Devices Limited
Chapter 6 Page 35 of 77
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
Table 2.7-4
Standard Timings
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.
2.7.3.1 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
Table 2.7-5
51N Element Blocking