[Answer] What Are the Differences Between Siemens PLCs and Omron PLCs?

[Answer] What Are the Differences Between Siemens PLCs and Omron PLCs?

In general, every PLC manufacturer has entry-level, mid-range, and high-end product lines. Siemens typically ranges from the smaller S7-200, 300, and 400 series to the newer S7-1200 and S7-1500 series, with the former being the upgraded version of the 200 series and the latter replacing the 300 and 400 series. Correspondingly, Omron’s lineup from small to large includes the CP, CJ, and CS series. At the same class level, product performance and pricing are generally quite close.

Differences:

1. In terms of market influence, Siemens’ market share and industry presence in the PLC field are far ahead of Omron’s. Siemens accounts for roughly 30% of the market, while Omron is under 10%, though these figures are only for reference.

2. In terms of after-sales service and documentation, Siemens established its 400 support hotline much earlier than Mitsubishi and Omron, and all of its documentation and tutorials can be downloaded in Chinese from its official website.

3. In terms of programming, both companies have their own programming software, and both support IEC-standard languages such as LAD and STL. From a usability perspective, Siemens software has its own structure and characteristics, making it somewhat harder for beginners to learn, and once you get used to it, it can be less natural to switch to other programming software. Omron’s programming software is relatively simpler and easier to learn. Of course, once you are familiar with either, the differences are not that significant.

4. In terms of communication protocols, Siemens mainly supports its own protocols such as PPI, MPI, and PROFIBUS, while Omron supports the Modbus protocol, which has been widely promoted by Schneider. Of course, both brands now also offer products that support Ethernet.

5. A common view is that Siemens PLCs are tougher and more durable than Japanese PLCs. However, this is also based largely on hearsay, and I do not have personal firsthand experience with it.

6. Overall, Siemens PLCs tend to feel more rigid and rule-based, while Japanese PLCs are somewhat more flexible. However, Siemens is more widely used, has more complete technical support, and offers a large amount of reference material, which gives it an inherent advantage over the latter.