Siemens SIPROTEC 7SJ80 User Manual

to the displacement voltage V
0
and compared with setting value RELEASE DIRECT.. The example is there-
fore suitable for ground fault direction in resonant grounded systems where quantity 3Ι0 · cos ϕ is relevant.
The directional limit lines are perpendicular to axis 3Ι0
real
.
[7sj6-richtungskennlinie-bei-cos-messung-101210, 1, en_US]
Figure 2-68 Directional characteristic for cos–ϕ–measurement
The directional limit lines may be rotated by a correction angle (address PHI CORRECTION) up to ± 45°.
Therefore, in grounded systems it is possible e.g. to increase sensitivity in the resistive-inductive range with a
rotation of –45°, or in case of electric machines connected to the busbar of an ungrounded power system in
the resistive- capacitive range with a rotation of +45° (see the following Figure). Furthermore the directional
limit lines may be rotated by 90° to determine ground faults and their direction in isolated systems.
Functions
2.12 Ground Fault Protection 64, 67N(s), 50N(s), 51N(s)
174 SIPROTEC 4, 7SJ80, Manual
E50417-G1140-C343-A8, Edition 12.2017

Siemens SIPROTEC 7SJ80 Specifications

General

Rated Frequency	50/60 Hz
Rated Current	1 A / 5 A
Operating Temperature	-25°C to +55°C
Storage Temperature	-40°C to +70°C
Current Transformer Inputs	4
Application	Protection of feeders, motors, transformers, and generators
Rated Voltage	100-240 V AC/DC
Communication Protocols	IEC 61850, Modbus, DNP3, IEC 60870-5-103
Display	Graphical LCD
Mounting	Flush mounting
Protection Functions	Overcurrent, Earth fault
Communication Interfaces	Ethernet, RS485
Housing	Plastic
Weight	Approx. 1.5 kg