1. CPU Modules
Model Digital I/O Analog I/O Max. Expansion Program Memory Data Memory High-Speed Counters Pulse Outputs
CPU SR20 12 In / 8 Out - 6 Modules 12 KB 8 KB 4 (100 kHz) 2 (100 kHz)
CPU ST30 18 In / 12 Out - 6 Modules 20 KB 12 KB 6 (100 kHz) 3 (100 kHz)
CPU SR40 24 In / 16 Out - 6 Modules 20 KB 12 KB 6 (100 kHz) 3 (100 kHz)
CPU ST60 36 In / 24 Out - 6 Modules 40 KB 16 KB 6 (100 kHz) 3 (100 kHz)
CPU CR40 24 In / 16 Out - No Expansion 20 KB 12 KB 6 (100 kHz) 3 (100 kHz)
2. Communication & Networking
Built-in Ports:

1 × RS485 (PPI, MPI, Freeport)

1 × Ethernet (10/100 Mbps, supports Modbus TCP, S7 protocol)

Optional Expansion:

Signal Board (SB): Adds RS485/RS232

Communication Module (CM): PROFIBUS-DP, Ethernet

3. Analog & Special Modules
Module Channels Resolution Input/Output Range
EM AE04 (Analog In) 4 12-bit 0-10V, 0-20mA
EM AQ02 (Analog Out) 2 12-bit 0-10V, 0-20mA
EM AM06 (Mix I/O) 4 In / 2 Out 12-bit ±10V, 0-20mA (In), 0-20mA (Out)
EM DR32 (Relay Out) 32 - 24V DC / 230V AC (5A)
4. High-Speed I/O & Motion Control
High-Speed Counters: Up to 6 channels (100 kHz)

Pulse Outputs: Up to 3 channels (100 kHz, for stepper/servo control)

PTO (Pulse Train Output): Supports linear interpolation

5. Power Supply & Environmental
Input Voltage:

AC Models: 85-264V AC

DC Models: 20.4-28.8V DC

Operating Temperature: 0°C to 55°C

Protection Class: IP20 (for cabinet installation)

Humidity: 5-95% (non-condensing)

6. Programming & Software
Software: STEP 7-Micro/WIN SMART (Free download)

Programming Languages: LAD (Ladder), FBD (Function Block), STL (Statement List)

Communication Protocols:

Modbus RTU (Slave/Master)

Modbus TCP

USS (for Siemens Drives)

7. Certifications & Standards
CE, UL, cULus

EMC: EN 61000-6-2 (Immunity), EN 61000-6-4 (Emissions)

Industrial: IEC 61131-2 (PLC standards)

8. Typical Applications
✔ Small Machine Control
✔ Packaging & Conveyor Systems
✔ HVAC & Building Automation
✔ Laboratory Equipment
✔ Renewable Energy Controls

Why Choose S7-200 SMART?
✅ Cost-Effective – Budget-friendly for small automation tasks
✅ Easy to Use – Integrated Ethernet for quick setup
✅ Flexible I/O – Expandable with analog, digital, and communication modules
✅ Strong Motion Control – Built-in high-speed I/O for simple positioning