Description

The Siemens S7-200 SMART SR20 is an entry-level PLC CPU designed for small-scale automation applications. It features 12 digital inputs and 8 relay outputs, operating on a 220 VAC power supply. This model is ideal for users who require basic logic control and AC output switching. The relay outputs make it compatible with a wide range of actuators, such as solenoid valves, contactors, and pilot lamps that operate on both AC and DC voltages. Despite being an economical model, the SR20 retains core capabilities like high-speed instruction execution and basic networking support through an RS-485 port. It supports expansion using signal boards, enabling analog input/output or additional communication ports if needed. Programmed via STEP 7 MicroWIN SMART, the SR20 is well-suited for beginners or for integration into systems where budget and space constraints are primary concerns. It provides stable, reliable operation in compact panels, lighting automation, and machine interlocks.