Siemens SIPROTEC 7SJ80 User Manual

Current Transformer Requirements
The requirements for phase current transformers are usually determined by the overcurrent time protection,
particularly by the high-current element settings. Besides, there is a minimum requirement based on experi-
ence.
The recommendations are given according to the standard IEC 60044-1.
The standards IEC 60044-6, BS 3938 and ANSI/IEEE C 57.13 are referred to for converting the requirement into
the knee-point voltage and other transformer classes.
D.1 Accuracy limiting factors 456
D.2 Class conversion 457
D.3 Cable core balance current transformer 458
D
SIPROTEC 4, 7SJ80, Manual 455
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