Software Engineer (PLC) -Control System Engineering

At Quest Global, it’s not just what we do but how and why we do it that makes us different. With over 25 years as an engineering services provider, we believe in the power of doing things differently to make the impossible possible. Our people are driven by the desire to make the world a better place—to make a positive difference that contributes to a brighter future. We bring together technologies and industries, alongside the contributions of diverse individuals who are empowered by an intentional workplace culture, to solve problems better and faster.

This position involves developing PLC and HMI control systems for semiconductor gas/chemical delivery equipment. Responsibilities include designing control logic, system integration, commissioning, and troubleshooting. The role involves designing control architectures based on customer requirements and leading the improvement of equipment stability and performance, as well as the standardization of automation.

As a Senior Engineer, Lead the software programming, system design, and technical direction for chemical and specialty gas delivery equipment used in semiconductors.

Proficient in PLC, HMI, C/C++, Java, and other PC-based languages at an expert level. Hold a technical vision for the assigned product areas in chemical equipment and translate complex requirements into scalable, high-performance, manufacturable solutions. Through cross-team collaboration, they contribute to engineering standardization and reliability and demonstrate technical leadership in both systems engineering and PLC software development.

Key Responsibilities

PLC Software Development

• Understand PLC Software Development
• Develop and maintain PLC software based on IEC 61131-3 standards.
• Design, program, test, and validate PLC logic for semiconductor gas and chemical delivery systems.
• Support Omron, Siemens, and LS PLC platforms.
• Develop reusable software modules and engineering standards

HMI & System Integration

• Configure and maintain HMI systems (Pro-face, MXon/M2I).
• Implement alarms, diagnostics, state monitoring, and data logging functions.
• Integrate PLC, HMI, instruments, motion devices, and network systems.

System Engineering 

• Analyze customer and product requirements and translate them into software and control system architecture.
• Define software-hardware interfaces and control philosophies.
• Support system design reviews and risk assessments.

Troubleshooting & RCA

• Investigate field issues and implement corrective actions.
• Lead root cause analysis (RCA) activities.
• Optimize system performance, reliability, and maintainability.

Manufacturing & Customer Support

• Support manufacturing, FAT, SAT, commissioning, and startup activities.
• Provide technical support during customer escalations.
• Develop manufacturing packages and technical documentation.

Cross-Functional Collaboration

• Work closely with Mechanical, Electrical, Quality, Project Management, and Manufacturing teams.
• Collaborate with global engineering teams on platform standardization and product improvements.
• Participate in engineering change management (ECR/ECO) activities.

Continuous Improvement 

• Drive software standardization and code modularization.
• Contribute to technology roadmaps for next-generation control systems.
• Mentor junior engineers and share technical best practices

We are known for our extraordinary people who make the impossible possible every day. Questians are driven by hunger, humility, and aspiration. We believe that our company culture is the key to our ability to make a true difference in every industry we reach. Our teams regularly invest time and dedicated effort into internal culture work, ensuring that all voices are heard.

We wholeheartedly believe in the diversity of thought that comes with fostering a culture rooted in respect, where everyone belongs, is valued, and feels inspired to share their ideas. We know embracing our unique differences makes us better, and that solving the worlds hardest engineering problems requires diverse ideas, perspectives, and backgrounds. We shine the brightest when we tap into the many dimensions that thrive across over 21,000 difference-makers in our workplace.

Minimum Qualifications

• Bachelor's degree in Electrical Engineering, Automation Engineering, Software Engineering, Computer Science, or related field.
• Minimum 5 years of PLC software development experience.
• Strong hands-on experience with: Omron / Siemens / LS PLC
• Experience with HMI development (Pro-face, MXon, M2I or equivalent).
• Knowledge of industrial communication protocols: Ethernet/IP, Modbus TCP/RTU, Profinet, EtherCAT
• Experience in troubleshooting and debugging industrial automation systems.
• Ability to communicate effectively in an international engineering environment

Preferred Qualifications 

• Experience with semiconductor equipment, gas delivery systems, chemical delivery systems, or process equipment.
• Experience supporting customer sites, installation, and commissioning activities.
• Experience with SCADA or industrial software platforms.
• Knowledge of functional safety and industrial cybersecurity.
• Experience leading technical projects or system architecture reviews.
• Experience collaborating with global engineering organizations.