Control Panel Design, Build & Software for a Three-Skid Gas Compression System
Sector:
Energy & Nuclear
Type:
New Build - Control System, Software
Platform:
Allen Bradley
Certification:
CE / UKCA
Summary
DelaControl delivered a complete control system for a three-skid gas compression installation, covering electrical design, panel build, FLEX I/O junction boxes, PLC and HMI software development, and pre-delivery testing across all three skids. The Allen Bradley ControlLogix platform was used throughout, with WEG variable speed drives, ATEX-rated intrinsic safety barriers for RTD inputs, a UPS-backed 24 V DC supply, and an IoT gateway for remote connectivity.
Challenge
A gas compression OEM required control systems for three compressor skids (Skid A, B and C). The customer's own engineering resource was committed elsewhere, so a capable external partner was needed to take on the full scope: electrical design for two of the three skids, procurement and build of all three control panels, and development of the PLC and HMI software across all skids.
Control documentation had been produced only for Skid A at the point of software engagement; Skids B and C were understood to follow the same control philosophy. No formal software design specification existed, so the software needed to be developed in line with a cause-and-effect and alarm-trip philosophy document, using donor HMI code supplied by the customer as a starting point.
Solution
DelaControl produced the full electrical design for two of the three skids using EPlan, building all three control systems against approved schematics at DelaControl's Bristol facility. Each system centres on a Rittal VX bayed enclosure (two 1200 W × 2000 H × 600 D mm sections, IP55) housing an Allen Bradley ControlLogix 1756 PLC — a 4-slot chassis for the primary rack and a 10-slot chassis for the I/O expansion rack — with dual Ethernet modules for network redundancy. Eight WEG CFW300 variable speed drives (up to 5.5 kW, 400 V) with Ethernet communication modules handle motor control, protected by Schneider TeSys GV2 motor circuit breakers. A PULS 24 V DC UPS system with dual 120 Ah batteries provides supply resilience, and an IXON IXrouter3 4G/Wi-Fi IoT gateway enables remote access.
Two FLEX I/O remote I/O nodes (JB10 and JB11) extend the system's reach: JB10 hosts three 8-channel RTD input modules behind 19 Eaton MTL7756AC ATEX-rated intrinsic safety barriers for safe-area/hazardous-area signal conditioning, alongside digital and analogue I/O; JB11 carries four 8-channel analogue input modules. Pepperl+Fuchs isolated switch amplifier barriers and a Pilz dual-channel safety relay are also included. Thermal calculations were carried out using Rittal Therm software, with a filter fan fitted to manage heat rise. A full drawing pack (general arrangements and schematics in EPlan and PDF), Declaration of Conformity (LVD and EMC directives, to BS EN 60204-1, BS EN 61439-1 and BS EN 61439-2), FAT schedule, and FAT certificate were produced. A Beijer X2 Pro 12-inch touchscreen HMI is fitted to each panel.
PLC software for all three skids was written in Studio 5000 (v33) and verified using Logix Emulate simulation prior to FAT. HMI software was developed using the customer's donor code as a basis and updated to reflect the control philosophy. On successful FAT, the complete software was handed over to the customer.
Key Facts
• Three compressor skid control systems designed, built, and tested
• Allen Bradley ControlLogix 1756 platform: 4-slot primary chassis plus 10-slot I/O expansion chassis per skid
• Two FLEX I/O remote nodes (JB10 and JB11) per skid with RTD, analogue, and digital I/O modules
• 19 × Eaton MTL7756AC ATEX intrinsic safety barriers for RTD signal conditioning
• Eight WEG CFW300 variable speed drives per skid (up to 5.5 kW, 400 V, with Ethernet modules)
• PULS 24 V DC UPS with dual 120 Ah batteries for supply resilience
• Pilz dual-channel safety relay and Pepperl+Fuchs isolated switch amplifier barriers included
• IXON IXrouter3 4G/Wi-Fi IoT gateway for remote access
• Beijer X2 Pro 12-inch touchscreen HMI per skid
• PLC software developed in Studio 5000 v33 and verified via Logix Emulate simulation
• Full EPlan drawing pack, Declaration of Conformity (LVD/EMC), FAT schedule and certificate delivered
• Rittal VX bayed enclosures, IP55, 1200 W × 2000 H × 600 D mm (two sections per skid)