Siemens Reyrolle 7SR5 - Page 427

If Phase Rotation ACB is selected in the CT/VT menu, the expected PPS and NPS are exchanged and the
output from a standard positive sequence test set will be considered as NPS.
Definite Time NPS Overcurrent (46DT)
If DTL setting is small, gradually increase current until element operates.
If DTL is large apply 0.9 times setting, check for no operation, apply 1.1 times setting, check operation.
Apply 2 times setting current if possible and record operating time.
Phase I
set
(Amps) DTL (sec) P.U. Current
Amps
Tolerance Operate Time
2 ⋅ I
set
Tolerance
NPS
Check correct indication, trip output, alarm contacts, waveform record.
Inverse Time NPS Overcurrent (46IT)
It will be advantageous to map the function being tested to temporarily drive the relevant pickup output in the
Pickup Config sub-menu in the Output Config menu as this will allow the Pickup led to operate for
the function.
Gradually increase current until Pickup LED operates.
Apply 2 times setting current and record operating time.
Apply 5 times setting current and record operating time.
Compare to calculated values for operating times.
P.U.
D.O. &
Timing
Tests
Ph. Dir Char.
(NI EI
VI LTI,
DTL)
I
set
(A) Tm Operate Current Operate Time
P.U.
(Amps)
D.O.
(Amps)
Tol 2 ⋅ I
set
(sec)
5 ⋅ I
set
(sec)
Tol
NPS
Calculated timing values in seconds for Tm = 1.0
Curve
2 ⋅ I
set
5 ⋅ I
set
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.
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
Fully Operated to Reset with Zero Current Applied
& Tm = 1 s
ANSI-MI 4.85
ANSI-VI 21.6
ANSI-EI 29.1
Functional Tests
9.10 Protection Functional Tests
Reyrolle 7SR5, Transformer Protection Device, Device Manual 427
C53000-G7040-C015-1, Edition 11.2019