Siemens Simatic S7 Series System Manual

Getting started
2.4 Changing the operating mode of the CPU
S7-200 SMART
36 System Manual, 09/2015, A5E03822230-AC
2.4
Changing the operating mode of the CPU
The CPU has two modes of operation: STOP mode and RUN mode. The status LEDs on the
front of the CPU indicates the current mode of operation. In STOP mode, the CPU is not
executing the program, and you can download program blocks. In RUN mode, the CPU is
executing the program; however, you can download program blocks.
Placing the CPU in RUN mode
1. Click the "RUN" button on either the PLC menu ribbon strip or on the program editor
toolbar:
2. When prompted, click "OK" to change the operating mode of the CPU.
You can monitor the program in STEP 7-Micro/WIN SMART by clicking the "Program Status"
button from the "Debug" menu ribbon strip, or from the program editor toolbar.
STEP 7-Micro/WIN SMART displays the values for the instructions.
Placing the CPU in STOP mode
To stop the program, click the "STOP" button and acknowledge the prompt to place the
CPU in STOP mode. You can also place a STOP instruction in your program logic to put the
CPU in STOP mode.

Siemens Simatic S7 Series Specifications

General

CPU	Varies by model (e.g., S7-300, S7-400, S7-1200, S7-1500)
Communication Interfaces	PROFIBUS, PROFINET, Ethernet, MPI
Programming	TIA Portal, STEP 7
Programming Languages	LAD, FBD, STL, SCL, GRAPH
I/O Modules	Digital, Analog, Specialty modules available
Operating Temperature	0°C to 60°C (standard models)
Mounting	DIN rail mounting
Operating Voltage	24V DC or 120/230V AC (varies by model)
Protection Class	IP20 (standard models)
Memory	Varies depending on the S7 model. Includes work memory (RAM) for program execution, load memory (EEPROM or Flash) for program storage, and system memory for operating system functions. Memory sizes range from kilobytes to megabytes.