Siemens Industry Online Support
Siemens AG
Entry type: Product note Entry ID: 4342429, Entry date: 07/23/1998

FM 355S and FM 455S - Product Information

  • Entry
  • Associated product(s)

Concerns products with the Catalog No.'s:                                   


6ES7 355-1VH10-0AE0   FM 355 for PID control                                

6ES7 355-1VH00-0AE0   FM 355 for PID control                                

6ES7 455-1VS00-0AE0   FM 455 for PID control                                



The pulse output of the step controller with and without position feedback  

can be blocked permanently under certain conditions. This causes the actua- 

tor to remain in its position irrespectively of the system deviation and it 

cannot be operated properly in manual mode either.                          


Preliminary remedy:                                                         


- If the minimum pulse duration is configured to be zero, the above error   

  will not occur.                                                           


- Since the step controller will not output pulses shorter than the sampling

  time of the controller, switching on a number of controllers and increas- 

  ing the resolution of the analog input to 14 bits will increase the min.  

  pulse duration and prevent the above error from occurring.                


We shall inform you as soon as the above problem has been eliminated by a   

new revision level.                                                         




Security information
In order to protect technical infrastructures, systems, machines and networks against cyber threats, it is necessary to implement – and continuously maintain – a holistic, state-of-the-art IT security concept. Siemens’ products and solutions constitute one element of such a concept. For more information about cyber security, please visit