The UE410-8DI module is an input extension with 8 inputs that can be linked by using the OR, AND or Bypass logic function to the respectively upstream UE410-MU/XU module. The 9 switch positions of the UE410-8DI rotary switch determine which safety components can be connected as well as which type of logic should be applied when communicating with the UE410-MU/XU. The input extension module acts exclusively on the next (UE410-MU/UE410-XU) module positioned to the left in the module structure, thus forming a function group.