Overcurrent Protection - Siemens SIPROTEC easy 7SJ45 Handbuch

Manual 7SJ45

Overcurrent protection

Setting ranges / increments for definite-time protection
(DT O/C 50/51)
Pickup current I>> (phases) 2 I
N
increments 0.5 I
Pickup current I> (phases); 0.5 to 6.2 I
three-phase supply; or ineffective, increments 0.1 I
see Note
Pickup current IE> 0.5 to 6.2 I
(earth calculated); or ineffective, increments 0.1 I
three-phase supply;
see Note
Delay times T I>> 0 to 1575 ms, increments 25 ms
Delay times T I> 0 to 6300 ms, increments 100 ms
The set times are pure delay times.
C53000-K1174-C001-7
to 20 I or ineffective,
N
N
N
N
N
N
Setting ranges / increments for inverse-time protection
(IEC 51 or ANSI 51)
Pickup current Ip (phases); 0.5 I
three-phase supply; or ineffective, increments 0.1 I
see Note
Pickup current IEp> (earth 0.5 I
calculated); or ineffective, increments 0.1 I
three-phase supply;
see Note
Delay times T Ip (IEC) 0.05 to 3.15 s,
increments 0.05 s
Delay times D (ANSI) 0.5 to 15.00 s,
increments 0.25 s
Note!
The device allows minimum setting values of 0.5 I
With single-phase supply, please observe the minimum setting values of
0.8 I (7SJ45XX-0*) or 1.3 I (7SJ45XX-1*) printed on the front panel.
N N
WARNING!
When setting the parameters, note that the maximum thermal overload
capability of the current path is 2 I
Technical Data
to 4 I
N N
N
to 4 I
N N
N
(three-phase supply).
N
.
N
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