User Manual

3RR2 current monitoring relays
4.3 Performance features of current monitoring relays
3UG4 / 3RR2 monitoring relays
44 Manual, 02/2013, NEB927043002000/RS-AA/002
4.3.2 Properties
Table 4- 4 Equipment of 3RR2 current monitoring relays
Feature Benefit 3RR21 Basic,
analog setting
3RR22 Standard,
digital setting
Reset function
• Enables manual or automatic
resetting of the monitoring relay
• Resetting directly on the device or
by disconnecting and reconnecting
the supply voltage (remote reset)
✓ ✓
ON-delay time
• Enables motor starting without
evaluation of the starting current
• Can be used to monitor motors with
lengthy startup
0 s to 60 s 0 to 99 s
Tripping delay time
• Prevents frequent warnings and
disconnection in response to
currents in the vicinity of the
thresholds
• Permits brief violations of thresholds
during operation
0 s to 30 s 0 s to 30 s
Operator controls and displays
• For setting thresholds and delay
times
• For selectable functions
• For fast and selective diagnostics
• Display for permanent indication of
measured values
LEDs and rotary
buttons
Display and buttons
Integrated contacts
• Allow the system or process to be
shut down in the event of an
irregularity
• Can be used to output signals
1 CO contact 1 CO contact
1 semiconductor
output