SIRIUS 3RF34 solid-state switching devices   
3.2 Product description 
  SIRIUS Innovations 
318  System Manual, 01/2011, A8E56203870002-03 
3.2.2  Applications 
Solid-state switching devices for switching motors  
The solid-state contactors for the wear-free and noiseless switching of motors are designed 
for the frequent switching on and switching off of AC drives up to 7.5 kW as well as for 
reversing up to 3.0 kW. The devices are fully insulated and can be mounted directly on motor 
starter protectors and overload relays or SIRIUS current monitoring relays, which makes 
them really easy to integrate into motor feeders.  
These 3-phase solid-state contactors are equipped with a 2-phase control which is 
particularly suitable for typical motor circuits without a connection to the neutral conductor. 
The integration of four current paths to form a single reversing circuit, accommodated in one 
enclosure, makes the solid-state reversing contactor a particularly compact solution. Unlike 
conventional systems which require two contactors, width can be reduced by up to 50% with 
the 3-phase solid-state reversing contactors. Devices with a width of 45 mm cover motors up 
to 2.2 kW and those with a width of 90 mm cover motors up to 3 kW.  
Integration in the SIRIUS modular system facilitates connection to a SIRIUS motor starter 
protector via a link module or to a 3RB30/3RB31 solid-state overload relay or a 3RR2 current 
monitoring relay without additional steps. As a result, fuseless or fused motor feeders can be 
implemented quickly and easily.  
Main features: 
●  Insulated enclosure with integrated heat sink 
●  Degree of protection IP20 
●  Integrated mounting foot for snapping on a DIN rail or mounting on a support plate 
●  Variety of connection systems 
●  Plug-in control connection 
●  LED to indicate control voltage 
Reference 
 
More information ...  Can be found in the chapter titled 
About link modules  Description (Page 348) 
About the overload relay  Overload relays (Page 485) 
About current monitoring relays  Current monitoring relays (Page 683)