The front connector has:

• Screw-type terminals, crimp contacts or spring-loaded terminals for connecting the wiring
• A removable cover to protect the cables.With writable wiring diagram on the inside and labeling plate on the outside.
• Cable grip
• Labeling plates:
  A labeling plate on the front connector, a wiring diagram on the inside of the cover and a labeling field on the outside
• Two-component coding key:
  When the front connector is plugged into the module for the first time, one part of the coding key latches into the front connector. The other part element remains on the module. The front connector can then only be plugged into signal modules with the corresponding part of the coding element.