You need a LOGO! Expansion Module when the inputs and outputs of the LOGO! Basic Module are not sufficient for your application.
Each LOGO! 9 Basic Module provides 8 inputs and 4 outputs. If your application requires more digital or analog signals, you can add suitable LOGO! Expansion Modules.
This is useful for applications that start small but may grow over time, or for applications that require additional sensors, switches, actuators or analog values.
Typical examples include small machine control, pumps, fans, lighting, access systems, building-related automation, control cabinets and small infrastructure applications.