Comparing Siemens vs Allen Bradley: Which PLC Platform Should You Learn?

The Siemens versus Allen-Bradley debate is the most common question in industrial automation training. Both platforms run billions of dollars worth of manufacturing equipment worldwide, and both create lucrative career opportunities for the professionals who master them. But they are not interchangeable, and the platform you learn first will shape your career trajectory. Here is a data-driven comparison to help you make the right choice. ## Market Share: Where Each Platform Dominates Understanding geographic market share is essential because it determines where the jobs are. Siemens holds 37 percent of the global PLC market — the largest share worldwide. The S7-1500 controller family and TIA Portal software platform dominate European manufacturing, and Siemens maintains strong positions in Asia-Pacific, the Middle East, and Latin America. If you are working outside North America, Siemens is the platform you are most likely to encounter. Allen-Bradley (Rockwell Automation) holds 35 to 40 percent of the North American market — the dominant share in the United States, Canada, and Mexico. ControlLogix and CompactLogix controllers are the standard in American automotive, food and beverage, consumer products, and general discrete manufacturing. If you are building your career in North America, Allen-Bradley is the platform most employers expect you to know. The rule of thumb in the industry: if you are building for a U.S. auto plant, you use Rockwell. If you are shipping a wind turbine to Europe or a bottling line to Asia, you use Siemens. ## Software: TIA Portal vs Studio 5000 The programming environment defines your daily workflow as an automation engineer. Both platforms have strengths and trade-offs: Siemens TIA Portal (currently V20, released 2024) is a unified engineering framework that integrates PLC programming, HMI development, drive configuration, and network management in a single application. This integration means you can configure an S7-1500 PLC, design a Comfort Panel HMI, set up SINAMICS drives, and commission the entire system without leaving TIA Portal. The drawback is complexity — TIA Portal has a steeper learning curve, typically requiring 40 to 60 hours for basic proficiency. The software also has slower compilation times than Studio 5000, which becomes noticeable on large projects. TIA Portal V20 introduced the Siemens Industrial Copilot, an AI assistant that can generate PLC code from natural language descriptions. Allen-Bradley Studio 5000 (currently V38, released September 2025) focuses specifically on PLC programming for ControlLogix and CompactLogix. Its tag-based architecture and flat program structure (Tasks, Programs, Routines) make it more approachable for beginners, with a typical learning curve of 24 to 40 hours. Studio 5000 excels at online editing — making live changes to a running controller — which is critical during commissioning and troubleshooting. HMI development requires a separate application (FactoryTalk View or FactoryTalk Optix), and drive configuration uses separate tools as well. This modular approach means more applications to learn but each one is more focused. Both platforms support all five IEC 61131-3 programming languages: Ladder Diagram, Function Block Diagram, Structured Text, Sequential Function Chart, and Instruction List (deprecated in newer versions). In practice, North American AB programmers use primarily Ladder Logic with Structured Text for calculations. Siemens programmers tend to use more Structured Text (called SCL in TIA Portal) and Function Block Diagram. ## Hardware: S7-1500 vs ControlLogix 5580 At the high end, both platforms deliver comparable performance: Siemens S7-1500 controllers achieve scan times of 1 to 3 milliseconds, with the premium 1518 series reaching sub-millisecond performance. The S7-1500 integrates safety functions directly into the CPU — F-CPUs run standard and safety programs simultaneously. Communication is built around Profinet with native OPC UA support for vertical integration. Allen-Bradley ControlLogix 5580 provides competitive scan times and supports up to 256,000 digital I/O points. Safety is handled through dedicated GuardLogix 5580 controllers that share the same chassis and backplane as standard controllers. Communication runs on EtherNet/IP with OPC UA available through add-on modules. For edge computing, Siemens offers SIMATIC Edge devices that run analytics alongside the PLC. Allen-Bradley's CompactLogix 5480 embeds Windows 10 IoT Enterprise directly alongside the Logix engine in one controller — a unique approach that puts computing and control in a single chassis. ## Industry Vertical Preferences Different industries have settled on preferred platforms based on historical relationships, installed base, and technical requirements: U.S. Automotive: Allen-Bradley dominant. Deep OEM relationships with GM, Ford, and tier-one suppliers. FactoryTalk platform integrates with plant-wide MES. European Automotive: Siemens dominant. Profinet networking standard. TIA Portal integrates with MES and ERP. Pharmaceutical: Both strong. Siemens edges ahead for batch process control and regulatory audit trails. Allen-Bradley strong for discrete packaging and inspection. Oil and Gas: Allen-Bradley in North America, Siemens globally. Regional installed base determines platform choice. Water and Wastewater: Both competitive. Often paired with platform-specific SCADA. Food and Beverage: Both competitive. Depends on region and machine builder preferences. Machine Building for export: Siemens preferred because global support networks and Profinet acceptance are wider outside North America. Chemical and Process: Siemens edges ahead with superior process automation features and native OPC UA. ## Career and Salary Impact Platform expertise directly affects earning potential: Allen-Bradley specialists in North America: $82,000 to $103,000 annually in full-time roles. Studio 5000 expertise adds a $5,000 to $8,000 premium. Contract rates: $58 to $75 per hour mid-level, $75 to $95 per hour senior. Siemens specialists: comparable salaries in European and global roles. In North America, Siemens expertise is rarer, which can command premium rates for the right projects. Dual-platform professionals who can program both Allen-Bradley and Siemens command 15 to 20 percent higher rates than single-platform specialists. On contract staffing platforms, dual-platform engineers earn $90 to $135 per hour because they can be deployed to any facility regardless of installed equipment. ## The Recommendation If you are based in North America and starting your career: learn Allen-Bradley first. The volume of available positions and contracts is higher, the learning curve is gentler, and you will be immediately employable at facilities in your area. If you want global mobility: learn Siemens first or second. With 37 percent global market share, Siemens expertise opens doors in Europe, Asia, the Middle East, and Latin America that Allen-Bradley alone does not. If you want maximum earning potential: learn both. The investment of 6 to 12 months learning your second platform pays for itself through expanded contract opportunities and premium rates. The fundamentals transfer between platforms — both use the same IEC 61131-3 programming concepts, both communicate over industrial Ethernet, and both follow similar control architecture principles. The automation industry projects 2.1 million unfilled manufacturing positions by 2030. Whether you choose Siemens, Allen-Bradley, or both, the demand for skilled PLC programmers will outlast any platform debate.