Principal PLC Controls Engineer

Staff / Principal PLC Controls Engineer – Test & Integration About the Role We are seeking a Staff/Principal-level PLC Controls Engineer to take ownership of PLC programming, controls integration, and commissioning for advanced test systems supporting a high-volume manufacturing environment.

Why This Role Is Open The company is scaling production toward a 225-unit build rate while simultaneously upgrading its test-stand infrastructure and controls architecture.

The existing PLC system is functional, but a significant amount of control logic currently resides directly in the PLC. The engineering team is transitioning portions of that functionality into product controllers and needs to establish reliable communication between the PLC and those controllers.

This is not a ground-up controls development project. The existing PLC code and functionality are already in place. The immediate need is for an experienced controls engineer who can step into the existing CODESYS/Structured Text codebase, understand how it works, determine what logic needs to be removed or modified, and implement the required PLC-to-controller communication with minimal direction.

At the same time, the team is updating its test stands. This engineer will help verify the updated systems before production units arrive, including instrumentation, sensors, PLC I/O, signal scaling, wiring, pinouts, and control-panel functionality.

The team is targeting a 225-unit build rate, so they need a true controls SME who can hit the ground running and help move the upgraded test infrastructure into production readiness.

What You'll DoDevelop, modify, debug, and maintain PLC programs using CODESYS and Structured Text (ST).Review and understand existing PLC code and control architecture with minimal direction.

Identify existing PLC logic that needs to be removed, modified, or transitioned to product controllers.

Develop PLC-to-product-controller communication and associated control logic.

Integrate product controllers into existing and newly updated test stands.

Modify proven PLC functionality while preserving existing system performance and reliability.

Troubleshoot PLC logic, I/O, instrumentation, sensors, wiring, pinouts, and control-panel issues.

Verify that instrumentation is properly connected to the PLC and that signals are reading, scaling, and outputting correctly.

Support electrical troubleshooting during system integration and commissioning.

Commission updated test stands and verify system functionality before production units arrive.

Work across controls, electrical, mechanical, systems, and manufacturing teams to resolve integration issues.

Serve as the controls SME during system integration, commissioning, and production readiness.

Identify technical issues quickly, determine root cause, and implement solutions independently.

Support improvements to controls architecture, test-system reliability, and production readiness.

Document PLC changes, system updates, troubleshooting activities, and commissioning results.

Technical EnvironmentCODESYSStructured Text (ST)
PLC programming and controls architecturePLC-to-product-controller communication

Product controllers

Industrial I/OSensors and instrumentation

Control panels and electrical systems

Automated test stands

System integration and commissioning

High-volume manufacturing equipment

Required Qualifications Staff, Principal, or equivalent senior-level PLC/Controls engineering experience.

Strong hands-on experience developing and modifying PLC programs.

Expert-level experience with Structured Text.

Professional experience with CODESYS or a comparable IEC 61131-3 PLC programming environment, with the ability to work directly in CODESYS.Demonstrated ability to enter an existing PLC codebase, understand the logic, and make changes independently.

Experience developing communication between PLCs and external/product controllers.

Strong understanding of PLC architecture, I/O, instrumentation, sensors, and control systems.

Strong electrical troubleshooting skills, including wiring, pinouts, control panels, sensors, and PLC I/O.

Experience with system integration, commissioning, or automated test equipment.

Ability to…