For example, a binary input going from a thermometer on a machine to a Simatic device might have the following meanings: The programs on the Simatic devices respond in real time to inputs from sensors on the controlled machines, and send output signals to actuators on the machines that directing their subsequent operation.ĭepending on the device and its connection modules, signals may be a simple binary value ('high' or 'low') or more complex. Microprocessors were introduced in 1973, allowing programs similar to those on general-purpose digital computers to be stored and used for machine control. Simatic devices have input and output modules to connect with controlled machines. Early Simatic devices were transistor-based, intended to replace relays attached and customized to a specific machine.
Siemens Simatic S7-300 PLC CPU with three I/O modules attachedĪs with other programmable logic controllers, Simatic devices are intended to separate the control of a machine from the machine's direct operation, in a more lightweight and versatile manner than controls hard-wired for a specific machine.
