We are seeking a highly experienced Allen-Bradley / Rockwell automation expert to assist with a pump station controls upgrade and documentation project. The primary objective is to replace obsolete controllers and HMIs while developing comprehensive documentation that will support the migration. Specifically, we are upgrading CompactLogix L32 controllers to L33, ControlLogix 55x1 controllers to 1756-L902TS, and replacing all PanelView 1250 terminals with PanelView 7 units throughout the station. Before executing the hardware migration, we require a detailed and professionally written Functional Specification and a complete Cause & Effects document for the entire station. The selected expert will review and reverse-engineer ten existing PLC programs (.ACD files) using Studio 5000 / RSLogix 5000. The PLCs include four Meter Skids, one Filters PLC, three Pumps PLCs, one ESD PLC, and one Station PLC. The task involves carefully analyzing control logic, sequences, interlocks, permissives, PID loops, valve and pump control strategies, ESD shutdown logic, alarm handling, cross-PLC dependencies, and HMI interactions. From this review, the freelancer will generate one consolidated Functional Specification document covering the full station architecture and subsystem operation, along with one comprehensive Cause & Effects matrix detailing triggers, detection logic, resulting actions, alarms, latching behavior, reset methods, and shutdown impacts. We will provide all .ACD files, along with a sample Functional Specification and a Cause & Effects template to streamline formatting and expectations. The ideal candidate must already own a licensed copy of Studio 5000 Professional and have significant experience working with ControlLogix and CompactLogix platforms, preferably within Oil & Gas or midstream pump station environments. This is not basic PLC programming work; we require someone capable of deeply understanding and documenting complex industrial control systems at an engineering level. The total project budget is fixed at $6,000, with completion required within four weeks. The project will be milestone-based with one milestone per week: Week 1 for system architecture review and high-level subsystem breakdown; Week 2 for draft Functional Specification; Week 3 for draft Cause & Effects document; and Week 4 for revisions and final deliverables. Please apply only if you have demonstrable Rockwell experience, have access to the required software, and can commit to the four-week schedule. Successful completion will lead to additional work related to PLC migration and HMI upgrades in future.