What is the relationship between sensors and I/O modules in PLC systems?

In a PLC system, I/O (Input/Output) modules play a crucial role in facilitating communication between the sensors and the PLC CPU. The sensors act as input devices that detect physical parameters, such as temperature, pressure, or motion, and convert them into electrical signals. These signals need to be processed by the PLC for automated control and decision-making.

I/O modules are specifically designed to receive these electrical signals from the sensors. When a sensor detects a condition, it sends a corresponding signal to the I/O module. The I/O module interfaces with the PLC CPU by transmitting this data in a format that the CPU can understand and process. This transmission is essential for the functioning of the PLC, as it enables the CPU to react to the sensors' readings based on pre-defined control logic.

This interdependence emphasizes that I/O modules are a vital link between the physical world (sensors) and the programmable logic within the CPU. The effectiveness of a PLC system greatly relies on the proper functioning of this relationship, making the statement about I/O modules transmitting sensor data to the PLC CPU accurate and fundamental to the operation of PLC systems.