Siemens SIMATIC SM 335 - Interference suppression filter for 24 V supply voltage

Connecting the Inputs and Outputs of the SM 335
2-10
SM 335 – High-Speed Analog Input/Output Module for the SIMATIC S7-300
6ES7 335-7HG00-8BA1
2.6 Interference suppression filter for 24 V supply voltage
Caution
The SM 335 module must always be used with an interference suppression filter to
obtain interference immunity for SIMATIC.
Interference
Interference may reach the SM 335 via the 24 V voltage supply. One cause of
such interference is the switching of loads connected to the 24 V circuit. The inter-
ference has a high-frequency content, which can impair proper functioning of the
SM 335.