SIRIUS 3RU2/3RB3 overload relays 
  5.10 Technical data 
SIRIUS Innovations 
System Manual, 01/2011, A8E56203870002-03 
549 
5.10.3.3  Conductor cross-sections main circuit 
Table 5- 45  Technical data for the main circuit connection, 3RB30/3RB31 overload relays 
Type  3RB30 1.,  
3RB31 1. 
3RB30 2.,  
3RB31 2. 
Size  S00  S0 
Width  45 mm  45 mm 
Connection type  Screw terminals with box terminal 
  Connection screw 
M3, Pozidriv size 2  M4, Pozidriv size 2 
  Operating tool 
∅ 5 to 6  ∅ 5 to 6 
  Tightening torque 
Nm  0.8 to 1.2  2 to 2.5 
  Conductor cross-sections (min./max.), 1-wire or 2-wire 
- Solid  mm
2
  2 x (0.5 to 1.5)
1)
 
; 2 x (0.75 to 2.5)
1)  
2 x (0.5 to 4)
1) 
 
2 x (1 to 2.5)
1) 
 
2 x (2.5 to 10)
1) 
 
- Finely stranded with end 
sleeve 
mm
2
  2 x (0.5 to 1.5)
1) 
 
2 x (0.75 to 2.5)
1)
 
2 x (1 to 2.5)
1)
 
; 2 x (2.5 to 6)
1) 
; max. 1 x 10 
 
- AWG cables, solid or stranded  AWG  2 x (20 to 16)
1)
 
2 x (18 to 14)
1)
 
2 x 12
1)
 
2 x (16 to 12)
1)  
2 x (14 to 8)
1)
 
Connection type  Spring-loaded connection 
  Operating tool 
∅ 3.0 x 0.5 and ∅ 3.5 x 0.5 
  Conductor cross-sections (min./max.) 
- Solid  mm
2
  1 x (0.5 to 4)  1 x (1 to 10) 
- Finely stranded without end 
sleeve 
mm
2
  1 x (0.5 to 2.5)  1 x (1 to 6) 
- Finely stranded with end 
sleeve (DIN 46228 Part 1) 
mm
2
  1 x (0.5 to 2.5)  1 x (1 to 6) 
 
- AWG cables, solid or 
stranded 
AWG  1 x (20 to 12)  1 x (18 to 8) 
1)
  If two different conductor cross-sections are being connected to one clamping point, both cross-sections must be 
located in the range indicated. If identical cross-sections are used, this restriction does not apply.