Operate and Reset Time
Attribute
Value
t
basic
Element basic operate time
20 ms ± 20 ms
t
op
Operate time
char = IEC-NI,
IEC-VI,
IEC-EI,
IEC-LTI
, ± 5 % or ± 30 ms
For char = IEC-NI: K = 0.14, α = 0.02
IEC-VI: K = 13.5, α = 1
IEC-EI: K = 80, α = 2
IEC-LTI: K = 120, α = 1
char = ANSI-MI,
ANSI-VI,
ANSI-EI
, ± 5 % or ± 30 ms
For char = ANSI-MI: A = 0.0515, B = 0.114,
P = 0.02
ANSI-VI: A = 19.61, B = 0.491, P = 2
ANSI-EI: A = 28.2, B = 0.1217, P = 2
char = DTL
t
delay
, ± 1 % or ± 20 ms
Reset time
ANSI decaying
, ± 5 % or ± 30 ms
For char = ANSI-MI: R = 4.85
ANSI-VI: R = 21.6
ANSI-EI: R = 29.1
IEC decaying
, ± 5 % or ± 50 ms
For char = IEC-NI: R = 9.7
IEC-VI: R = 43.2
IEC-EI: R = 58.2
IEC-LTI: R = 80
t
reset
t
reset
, ± 1 % or ± 20 ms
Repeatability
± 1 % or ± 20 ms
Overshoot time
< 40 ms
Disengaging time
< 50 ms
Technical Data
10.17 51G Time-Delayed Earth Fault – Measured
482
Reyrolle 7SR5, Transformer Protection Device, Device Manual
C53000-G7040-C015-1, Edition 11.2019