Technical Data
4.7 Time Overcurrent Protection
SIPROTEC, 7SD80, Manual
E50417-G1140-C474-A1, Release date 09.2011
302
4.7
Time Overcurrent Protection
Operating Modes
Characteristic Curves
High-Set Current Elements
As emergency overcurrent protection or backup overcurrent protection
Emergency Overcurrent Protection
Effective when the differential protection system is blocked (e.g. because of a failure
of the device communication)
Backup overcurrent protection
operates independent of any events
Definite dime stages (definite)
I
Ph
>, 3
I
0
>,
I
Ph
>>, 3
I
0
>>,
I
Ph
>>>, 3
I
0
>>>,
I
Ph
>
dir
, 3
I
0
>
dir
,
I
Ph
>>
dir
, 3
I
0
>>
dir
Inverse time elements
I
P
, 3
I
0P
;
I
Pdir
, 3
I
0Pdir
; a characteristic curve according to
Figure 4-3 to 4-5 can be selected.
Pickup value 50-B1 PICKUP
(phases)
for
I
Nom
= 1 A
0.10 A to 25.00 A
or
∞
(ineffective)
Increments 0.01 A
for
I
Nom
= 5 A
0.50 A to 125.00 A
or
∞
(ineffective)
Pickup value 50N-B1 PICKUP
(ground)
for
I
Nom
= 1 A
0.05 A to 25.00 A
or
∞
(ineffective)
Increments 0.01 A
for
I
Nom
= 5 A
0.25 A to 125.00 A
or
∞
(ineffective)
Pickup value
(directional phases)
for
I
Nom
= 1 A
0.10 A to 25.00 A
or
∞
(ineffective)
Increments 0.01 A
for
I
Nom
= 5 A
0.50 A to 125.00 A
or
∞
(ineffective)
Delays
(directional elements)
0.00 s to 30.00 s
or
∞
(ineffective)
Increments 0.01 s
0.00 s to 30.00 s
or
∞
(ineffective)
Increments 0.01 s
Delay 50-B1 DELAY
(phases)
0.00 s to 30.00 s
or
∞
(ineffective)
Increments 0.01 s
Delay 50N-B1 DELAY
(ground)
0.00 s to 30.00 s
or
∞
(ineffective)
Increments 0.01 s
Dropout ratio
approx. 0.93 for
I
/
I
Nom
≥
0.5
Pickup times
minimum
30 ms
typical 32 ms
maximum 35 ms
Dropout times
minimum
33 ms
typical 35 ms
maximum 38 ms
Tolerances
Currents
3 % of setting value or 1 % nominal current
Times
1 % of setting value or 10 ms
The set times are pure time delays
