Siemens Reyrolle 7SR5 Manual page 437

Element Blocking
The Calculated Earth Fault elements can be blocked by Binary Input Inhibit, VT Supervi-
sion and Inrush Detector operation. The characteristic can be made non-directional by VT Supervi-
sion. This functionality should be checked.
Element
51N-1
51N-2
51N-3
51N-4
50N-1
50N-2
50N-3
50N-4
ANSI Reset
If the element is configured as an ANSI characteristic, it may have an ANSI decaying reset delay applied.
ANSI reset times from operated condition to fully reset are as follows for zero applied current and Tm = 1.0.
The reset curve characteristic type and Tm is defined by the operating characteristic.
Curve
ANSI-MI
ANSI-VI
ANSI-EI
Apply current in the following sequence, a) 2 times setting for a time to ensure element operation, b) Zero
current for the reset time above (xTm), c) 2 times setting for a time to ensure element operation. Check that
the second operation (c) is similar to the first (a) and in line with the expected operate time for the element at
this current level.
Repeat the test with the reset time (b) reduced to 50 % of the previous value. Ensure that the second operate
time (c) is 50 % of the first (a) operate time.
Operate Time
(expected)
Check correct indication, trip output, alarm contacts, waveform record.
IEC Reset
If the element is configured as an IEC characteristic, it may have an IEC (decaying) reset delay applied.
IEC reset times from operated condition to fully reset are as follows for zero applied current and Time multi-
plier (Tm) = 1.0. The reset curve characteristic type and Tm is defined by the operating characteristic.
Curve
IEC-NI
IEC-VI
IEC-EI
IEC-LTI
Apply current in the following sequence, a) 2 times setting for a time to ensure element operation, b) Zero
current for the reset time above (xTm), c) 2 times setting for a time to ensure element operation. Check that
the second operation (c) is similar to the first (a) and in line with the expected operate time for the element at
Reyrolle 7SR5, Transformer Protection Device, Device Manual
C53000-G7040-C015-1, Edition 11.2019
BI Inhibits
Reset Time Operate Time
(calculated) (measured)
First test (c)
9.10 Protection Functional Tests
VTS Action
Fully Operated to Reset with Zero Current Applied
& Tm = 1 (s)
4.85
21.6
29.1
50 % Reset Time 50 % Operate
(calculated) Time (calcu-
lated)
Fully Operated to Reset with Zero Current Applied
& Tm = 1 (s)
9.7
43.2
58.2
80
Functional Tests
81HBL2 Inhibit
50 % Operate
Time (meas-
ured)
Second Test (c)
437