Siemens SIPROTEC 7SJ80 User Manual

[stoerfallverlauf-ohne-stromkriterium-260602-kn, 1, en_US]
Figure 2-45 Typical fault profile for source side connection of the voltage transformer (without current
supervision)
Figure 2-46shows a fault profile for a load side connection of the voltage transformers. When the circuit
breaker is open, the voltage disappears (the voltage remains below the pickup setting), and current supervi-
sion is used to ensure that pickup drops out after the circuit breaker has opened (BkrClosed I MIN).
After the voltage has dropped below the pickup setting, tripping is initiated after time delay 27-1 DELAY.
When the circuit breaker opens, voltage decreases to zero and undervoltage pickup is maintained. The current
value also decreases to zero so that current criterion is reset as soon as the release threshold (BkrClosed I
MIN) is exceeded. Pickup of the protection function is also reset by the action of the AND-combination of
voltage and current. As a consequence, energization is admitted anew when the minimum command time
elapsed.
Functions
2.6 Voltage Protection 27, 59
SIPROTEC 4, 7SJ80, Manual 125
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