This document introduces Siemens' SIMATIC S7-300 series programmable controllers and related components. The series features modularity, fanless design, and high flexibility, making it suitable for medium-sized automation control tasks.
The Siemens S7-300 is a modular programmable logic controller designed for medium‑performance automation tasks. It offers a flexible rack system that can be expanded with a wide range of CPU, I/O, function and communication modules.
The document describes the hardware structure, installation guidelines, module types, communication interfaces such as MPI, PROFIBUS‑DP and industrial Ethernet, and presents technical data for individual modules and accessories.
| Power supply voltage (SM 321 modules) | 120VAC |
|---|---|
| IP protection level (FM STEPDRIVE) | IP20 |
| Motor connection voltage (FM STEPDRIVE) | 3 x 325V |
| Maximum cable length (FM STEPDRIVE) | 50 m |
A S7-300 system can hold up to 32 modules across four racks, with a maximum of 8 modules per rack.
Each rack (CR/ER) can accommodate up to 8 modules.
The standard version operates from 0 °C to 60 °C, while the extended version works from –25 °C to +60 °C.
The extended version is rated for –25 °C to +60 °C.