The SB31 interface board is used in the SIMADYN D system as changeover function for the SB30 and SA30 output boards. The SB30 and SA30 interface boards switch the output signals of two  redundant SIMADYN D systems over when a system fails. The SB31 interface board evaluates up to  eight output signals of the two redundant SIMADYN D systems, and supplies the changeover signal  for the SB30 and SA30 interface boards when the active system fails. If the redundant system has  also failed, a changeover is not made. The eight associated binary inputs of the interface board must  be at a high signal level in order to be able to identify correct operation of the SIMADYN D system.  The SIMADYN D system is identified as being faulty if one input does not have a high signal level. 

User Manual for Interface board SB31 has 3 editions:
  • Interface board SB31 - 11.1993
  • Interface board SB31 - 09.1994
  • Interface board SB31 - 05.1995
Siemens Teleperm XP (T2000)