Siemens S7-200 SMART PLC CPU SR30 & ST30 – Technical Specifications

The Siemens S7-200 SMART CPU SR30 AC/DC/RLY and CPU ST30 DC/DC/DC are compact, high-performance PLCs designed for industrial automation, machine control, OEM equipment, and process automation. Both models provide powerful processing performance, built-in Ethernet communication, high-speed counters, pulse outputs, and flexible expansion capabilities.

Product Overview

Feature	CPU SR30 AC/DC/RLY	CPU ST30 DC/DC/DC
Order Number (MLFB)	6ES7 288-1SR30-0AA0	6ES7 288-1ST30-0AA0
Power Supply	85–264 VAC	20.4–28.8 VDC
Digital Inputs	18	18
Digital Outputs	12 Relay Outputs	12 Transistor (MOSFET) Outputs
Ethernet Port	1 × 10/100 Mbps	1 × 10/100 Mbps
RS485 Port	1 Built-in	1 Built-in
Optional Port	RS232/RS485 Signal Board	RS232/RS485 Signal Board
Program Memory	18 KB	18 KB
Data Memory	12 KB	12 KB
Dimensions	110 × 100 × 81 mm	110 × 100 × 81 mm
Weight	435 g	375 g

Key Features

Genuine Siemens S7-200 SMART PLC
Built-in Ethernet (10/100 Mbps)
Built-in RS485 Communication
18 Digital Inputs
12 Digital Outputs
High-Speed Counters up to 200 kHz
Pulse Outputs up to 100 kHz
Expandable up to 6 I/O Modules
Supports 1 Signal Board
Micro SDHC Card Support
Real-Time Clock with Super Capacitor Backup
Suitable for HMI, SCADA and Industrial Automation
Programming with STEP 7 Micro/WIN SMART

Memory & CPU Performance

Specification	Value
Program Memory	18 KB
Data Memory	12 KB
Retentive Memory	Up to 10 KB
Bit Memory	256 Bits
Process Image	256 Inputs / 256 Outputs
Analog Image	56 AI / 56 AQ Words
Local Memory	64 Bytes per Program
Boolean Execution	0.15 µs
Word Operation	1.2 µs
Real Math	3.6 µs

Digital I/O

Digital Inputs

18 Digital Inputs
24 VDC Input Voltage
Input Current: 4 mA per point
High-Speed Counter Support
Single Phase: 4 × 200 kHz
Quadrature: 2 × 100 kHz
Maximum Cable Length:
- Shielded: 500 m
- Unshielded: 300 m

Digital Outputs

CPU SR30 AC/DC/RLY

12 Relay Outputs
Output Voltage:
- 5–250 VAC
- 5–30 VDC
Rated Output Current:
- 2 A per output
- 10 A per common
Relay Mechanical Life:
- 10 Million Operations
Electrical Life:
- 100,000 Operations

CPU ST30 DC/DC/DC

12 Transistor Outputs
MOSFET Source Type
Output Voltage:
- 20.4–28.8 VDC
Rated Current:
- 0.5 A per output
- 6 A per common
Pulse Output:
- 3 × 100 kHz

High-Speed Functions

Function	Specification
High-Speed Counters	4
Single Phase	4 × 200 kHz
Quadrature	2 × 100 kHz
Pulse Outputs	3 × 100 kHz
Pulse Capture Inputs	12
Cycle Interrupt	2 (1 ms Resolution)
Edge Interrupt	4 Rising + 4 Falling

Communication

Feature	Specification
Ethernet	10/100 Mbps
Serial Port	RS485
Optional Port	RS232 / RS485
Ethernet Connections	Up to 8 HMI
Programming Connection	1
CPU Communication	8
GET/PUT Active	8
GET/PUT Passive	8
HMI via RS485	Up to 4