Description 
  3.6 Accessories and order number scheme 
SIRIUS 3RM1 motor starter 
Manual, 11/2013, A5E0345285095020A/RS-AB/002 
45 
Device connectors 
Function 
The device connectors can be used to loop through a common control supply voltage of 24 V 
DC to reduce wiring complexity between the individual motor starters (3RM1...-.AA04). 
Moreover, Failsafe motor starters with a 24 V control supply voltage (3RM11...-.AA04 / 
3RM13...-.AA04) can be interfaced to one 3SK1 safety relay as a group via device 
connectors. 
The device connectors can either be snapped onto a standard mounting rail or can be 
screwed onto a flat mounting wall. 
If the motor starters are not to be interconnected side-by-side, device daisy chain connectors 
must be used for the gaps, e.g. for thermal reasons (see "Derating (Page 51)"). 
The device connectors do not transfer commands.  
 
Table 3- 4  Order numbers for device connectors for 3RM1 motor starters 
 
Device connector for 3RM1 motor starters,  
22.5 mm wide 
3ZY1212-2EA00 
Device connector for looping through 
signals,  
22.5 mm wide 
3ZY1212-2AB00 
Device termination connector for 3RM1 
motor starters,  
22.5 mm wide 
including left cover for the first device 
connector in the system configuration 
3ZY1212-2FA00 
Use of device connectors exclusively for the 24 V DC control supply voltage 
By using device connectors, several 3RM1...-.AA04 motor starters can be jointly supplied 
with a control supply voltage of 24 V DC. This requires the control supply voltage to be 
applied to the A1 and A2 terminals of only one motor starter. 
Up to ten motor starters can be connected to one 24 V DC control supply voltage with device 
connectors. The 24 V DC control supply voltage must be within the operating range of 0.9 to 
1.1 for this purpose. If the full operating range of 0.8 to 1.25 is to be used, no more than five 
3RM1...-.AA04 motor starters can be used. Otherwise, the infeed must be repeated for every 
5th 3RM1 motor starter. 
The last motor starter in a row can be placed on a device termination connector.