User Manual

3RR2 current monitoring relays
4.4 3RR21 current monitoring relays
3UG4 / 3RR2 monitoring relays
46 Manual, 02/2013, NEB927043002000/RS-AA/002
4.4 3RR21 current monitoring relays
4.4.1 Operator controls and connection terminals
Front view / terminal labeling (basic version)
Front view Description
Position digits
①
Connection for contactor mounting or for stand-alone
assembly
②
Rotary button for setting the threshold for overshoot "I▲"
③
Rotary button for setting the threshold for undershoot "I▼"
④
Sliding switch "Memory" for selecting the reset response
parameter (manual/autoreset):
⑤
Control current terminal (removable):
The control circuit can be connected using either the screw-
type or the spring-loaded connection system.
⑥
Primary current terminal (permanently connected) :
The main circuit can be connected using either the screw-type
or the spring-loaded connection system.
⑦
Label
⑧
Device order number
⑨
Rotary button for startup delay time "onDel (s)"
⑩
Rotary button for tripping delay time "Del (s)"
⑪
Status display via "Ready" LEDs (green) for auxiliary voltage
and "Fault" (red) for switching state
Terminal labels
B1 Supply voltage ∼/+
B2 Supply voltage ∼/-
32 Output relay K1 changeover contact NC contact
31 Output relay K1 changeover contact root
34 Output relay K1 changeover contact NO contact
2T1, 4T2, 6T3 Main circuit terminals
14 / 22 Feed-through contactor auxiliary switch (S00)
,Ⴃ
,Ⴍ
a
B
BB






  
7
7
7

$
2
,











A2 Feed-through contactor coil terminal (S00)
You will find additional information on the connection terminals and the permissible
conductor cross-sections in Chapter "Connection methods (Page 19)".
You will find information on connecting in Chapter "Circuit diagrams (Page 50)".