User Manual

3RR2 current monitoring relays
4.3 Performance features of current monitoring relays
3UG4 / 3RR2 monitoring relays
Manual, 02/2013, NEB927043002000/RS-AA/002
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4.3.3 Configuration of load feeders
Table 4- 5 Load feeders with 3RR2 current monitoring relays
Feature Benefit 3RR21 Basic,
analog setting
3RR22 Standard,
digital setting
Short-circuit-proof up to 100 kA at 690 V
(in conjunction with the appropriate fuses
or the appropriate motor starter
protector)
• Provides optimum protection
of the loads and operating
personnel in the event of short
circuits due to insulation faults
or faulty switching operations
✓ ✓
Electrical and mechanical matching to
3RT2 contactors
• Simplifies configuration
• Reduces connection outlay
and costs
• Enables stand-alone assembly
as well as space-saving direct
mounting
✓ ✓
Spring-loaded connection system for
main circuit (option) and auxiliary circuit
(option)
• Enables fast connections
• Ensures that connections are
vibration-resistant
• Enables maintenance-free
connections
✓ ✓
4.3.4 Combinations with 3RT20 contactor
Monitoring relay
type
Current range 3RT20 1 S00 contactors
3/4/5.5/7.5 kW
3RT20 2 S0 contactors
5.5/7.5/11/15/18.5 kW
3RR21 41 1.6 to 16 A ✓ (with stand-alone assembly support)
3RR22 41 1.6 to 16 A ✓ (with stand-alone assembly support)
3RR21 42 4.0 to 40 A (with stand-alone assembly support) ✓
3RR22 42 4.0 to 40 A (with stand-alone assembly support) ✓