SIRIUS 3RT2 contactors/contactor assemblies 
  2.7 Accessories 
SIRIUS Innovations 
System Manual, 01/2011, A8E56203870002-03 
179 
2.7.4  EMC suppression module 
2.7.4.1  Description 
The EMC interference suppression module for size S00 contactors reduces the high-
frequency components and the voltage level of a "counter-source voltage" in three phases. 
This results in the following advantages:  
●  Reduction of arcing: 
The connection between the main current path and the EMC suppression module 
enables arcing, which is responsible for contact erosion and the majority of clicking 
noises, to be reduced; this in turn ensures an EMC-compliant design. 
●  Increased operational reliability: 
Since the EMC suppression module achieves a significant reduction in radio-frequency 
components and the voltage level in three phases, the contact durability is extended 
considerably. This makes an important contribution towards enhancing the reliability and 
availability of the system as a whole. 
●  Omission of fine graduation: 
There is no need for fine graduations within each performance class, as smaller motors 
inherently have a higher inductance, so that one solution is adequate for all fixed-speed 
operating mechanisms up to 5.5 kW. 
Versions 
Two electrical versions of the EMC suppression module are available. 
Table 2- 32  Versions of the EMC suppression module 
Design of the EMC suppression module  Order number 
RC circuit  3RT2916-1PA 
Varistor circuit  3RT2916-1PB