CHAPTER 6: SETPOINTS
S3 Protection
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
Courtesy of NationalSwitchgear.com
The 350 protection elements are organized in two identical setpoint groups: Setpoint
Group 1 and Setpoint Group 2.
Each Setpoint Group has the same protection functions, depending on the relay order
code. These protection functions include:
•
Phase Timed Overcurrent (Phase TOC)
•
Phase Instantaneous Overcurrent (Phase IOC)
•
Ground Timed Overcurrent (Ground TOC)
•
Ground Instantaneous Overcurrent (Ground IOC1, Ground IOC2)
•
Ground Directional(Ground Dir)
•
Neutral Timed Overcurrent (Neutral TOC)
•
Neutral Instantaneous Overcurrent (Neutral IOC1, Neutral IOC2)
•
Neutral Directional(Neutral Dir)
•
Negative Sequence Overcurrent (Negative Seq OC)
•
Phase Undervoltage (Phase UV)
•
Phase Overvoltage (Phase OV)
•
Neutral Overvoltage (Neutral OV)
•
Negative Sequence Overvoltage (Negative Seq OV)
•
Auxiliary Undervoltage (Auxiliary UV)
•
Auxiliary Overvoltage (Auxiliary OV)
•
Underfrequency 1, Underfrequency 2
•
Overfrequency 1, Overfrequency 2
•
Thermal Model
S3 PROTECTION
6–53