Specifications

Introducing the S7-200 Micro PLC
1-4
S7-200 Programmable Controller System Manual
C79000-G7076-C233-01
1.2 Major Components of the S7-200 Micro PLC
An S7-200 Micro PLC consists of an S7-200 CPU alone or with a variety of
optional expansion modules.
S7-200 CPU
The S7-200 CPU combines a central processing unit (CPU), power supply, and
discrete I/O points into a compact, stand-alone device.
 The CPU executes the program and stores the data for controlling the
automation task or process.
 Additional I/O points can be added to the CPU with expansion modules up to
the physical size limits listed in Table 1-1.
 The power supply provides electrical power for the base unit and for any
expansion module that is connected.
 The inputs and outputs are the system control points: the inputs monitor the
signals from the field devices (such as sensors and switches), and the outputs
control pumps, motors, or other devices in your process.
 The communications port allows you to connect the CPU to a programming
device or to other devices.
 Status lights provide visual information about the CPU mode (RUN or STOP),
the current state of the local I/O, and whether a system fault has been
detected.
 Some CPUs provide a real-time clock as a built-in feature, while other CPUs
require the real-time clock cartridge.
 A plug-in serial EEPROM cartridge provides a means to store CPU programs
and transfer programs from one CPU to another.
 A plug-in battery cartridge provides extended retention of data memory in RAM.