User Manual

3RR2 current monitoring relays
4.4 3RR21 current monitoring relays
3UG4 / 3RR2 monitoring relays
50 Manual, 02/2013, NEB927043002000/RS-AA/002
Required tools
The same screwdriver can be used to set the parameters as for mounting the current
monitoring relays.
4.4.4 Diagnostics
Status display
On the current monitoring relay with analog setting, two status LEDs indicate the operating
state:
● FAULT (red)
● READY (green)
Display Meaning
FAULT off Measured value is within range limits
FAULT steady on Device has tripped
FAULT flashing slowly Delay time is running
FAULT flashing rapidly Cable break/phase failure detected
READY off Voltage is not applied at B1 - B2
READY on Voltage is applied at B1 - B2
You will find more information about the LED display and its various settings in Chapter
"Function (Page 47)."
4.4.5 Circuit diagrams
Internal circuit diagrams 3RR21
3RR2141-1A.30 3RR2141-2A.30, 3RR2142-.A.30
/ / / %$&'& 
7 7 7 %    $
Current monitoring relay, 1 CO contact, 2-
phase
/ / / %$&'& 
7 7 7 %  
Current monitoring relay, 1 CO contact, 2-
phase