User Manual

System overview
3.5 Overview of the functions
3UG4 / 3RR2 monitoring relays
Manual, 02/2013, NEB927043002000/RS-AA/002
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3.5 Overview of the functions
3.5.1 3RR2 current monitoring relays
Table 3- 15 Functions of the 3RR21 / 3RR22 current monitoring relays for analog and digital setting
Current monitoring relay
Function
3RR21 3RR22
Current monitoring
Monitoring for undercurrent 2p 3p
Monitoring for overcurrent 2p 3p
Apparent current monitoring ✓ ✓
Active current monitoring — ✓
Range monitoring 2p 3p
Monitoring for phase failure, wire break 2p 3p
Monitoring for phase sequence — ✓
Internal ground-fault detection (fault current
monitoring)
— ✓
Blocking current monitoring — ✓
Supply voltage
Self-powered, without auxiliary voltage — —
Externally powered, with auxiliary voltage ✓ ✓
✓: Function available
2p: Monitoring is 2-phase
3p: Monitoring is 3-phase
— : Function not available