SIRIUS 3RU2/3RB3 overload relays 
  5.6 Mounting 
SIRIUS Innovations 
System Manual, 01/2011, A8E56203870002-03 
509 
5.6.3  Mounting/Disassembly 
Direct mounting on 3RT contactor 
The diagram below shows an example mounting scenario based on mounting the 
3RU21 thermal overload relay, size S0, on the 3RT2 contactor. The contactor/overload relay 
combinations can be snapped onto 35 mm DIN rails according to DIN EN 50022.  
Table 5- 14  Mounting the 3RU21 overload relay with a screw-type connection system  
Step  Operating instruction  Figure 
1  Push the overload relay into the contactor 
from below. Attach the two hooks on the 
overload relay to the two openings on the rear 
of the contactor. This pushes the main current 
contacts into the corresponding socket 
contacts on the contactor. 
2  Screw the contacts tight. 
Check that the cable is clamped tight.