Onsite Controls Engineer – Rockwell PLC & OT Networking

INS3 LLC; Missouri; On-site; USD 85,000 - 115,000; Full time

Job summary

INS3 LLC is seeking a hands-on Controls Engineer to act as resident technical resource at a Local Wastewater Utility in the St. Louis area. You'll program, integrate, commission, and support Rockwell Automation PLC systems and their industrial networks across treatment facilities.

The role focuses on Rockwell PLC and network communications work onsite. Some exposure to GE Proficy iFIX is a plus, but training will be provided.

Qualifications

• 3–5+ years hands-on Rockwell PLC programming experience (ControlLogix / CompactLogix, Studio 5000).
• Working knowledge of EtherNet/IP and industrial network configuration.
• Comfortable working in active plant/field environments and troubleshooting live systems.
• Strong communication skills and a professional, customer-facing demeanor.
• Valid driver's license and ability to travel to sites throughout the service area.
• Ability to pass a background check and any client-required site clearances.

Responsibilities

• Develop, configure, test, and commission Rockwell PLC applications (ControlLogix / CompactLogix) using Studio 5000 / RSLogix 5000.
• Design, configure, and troubleshoot industrial network communications, including EtherNet/IP, managed industrial switches (e.g., Stratix / Cisco), VLAN segmentation, and device-level networking.
• Diagnose and resolve control system and network faults in the field to minimize process downtime.
• Support, maintain, and (with training) develop GE Proficy iFIX HMI/SCADA applications.
• Perform onsite integration, startup, and commissioning at facilities (treatment plants, pump/lift stations, and remote sites).
• Create and maintain project documentation: functional specifications, I/O lists, network diagrams, test plans, and as-built records.
• Apply OT/ICS cybersecurity best practices in line with INS3 LLC standards.
• Coordinate closely with operations and engineering staff, communicating status, risks, and resolutions clearly.
• Adhere to all safety protocols for working in a water/wastewater environment.

Skills

Rockwell PLC

EtherNet/IP

Studio 5000

Industrial switches

Tools

RSLogix 5000

Stratix

Cisco switches

Job description

INS3 LLC is seeking a hands-on Controls Engineer to act as resident technical resource at a Local Wastewater Utility in the St. Louis area. You'll program, integrate, commission, and support Rockwell Automation PLC systems and their industrial networks across treatment facilities.

The role focuses on Rockwell PLC and network communications work onsite. Some exposure to GE Proficy iFIX is a plus, but training will be provided.