Performance Level D Safety System for Scissor Lift and Access Gate Interlocking
Sector:
Food & Beverage
Type:
Safety, Software
Platform:
Allen Bradley
Certification:
CE / UKCA
Summary
DelaControl designed, built, programmed, and commissioned a Performance Level D safety control system to interlock a scissor lift platform and access door against the status of two access gates at a UK food production facility.
Challenge
A scissor lift platform and associated access door required a safety system to prevent movement unless two access gates were confirmed closed and locked. The customer needed a complete engineered solution — hardware, software, and safety assessment — designed to an appropriate performance level under BS EN ISO 13849.
No ISO 12100 risk assessment had been completed at the time of enquiry, and no Software Design Specification existed for the project, so the safety performance level target needed to be established and documented as part of the engagement.
Solution
DelaControl designed and built a safety control panel based on an Allen Bradley Compact GuardLogix 5380 safety PLC (SIL2/PLd rated), paired with POINT Guard I/O safety input and output modules. The panel was housed in an IP66-rated steel enclosure and included an Allen Bradley HMI for operator interaction. A separate stainless steel pushbutton station was also built, housing directional controls and status indication.
PLC software was written in Allen Bradley Studio 5000, implementing the gate-interlock logic to a Performance Level D target in accordance with BS EN ISO 13849. A BS EN 13849 assessment was produced to demonstrate the performance level achieved.
Full documentation was provided including AutoCAD electrical drawings, a Factory Acceptance Test (FAT) schedule and signed certificate, and a CE Declaration of Conformity referencing BS EN 60204, BS EN 61439-1, and BS EN 61439-2. DelaControl carried out installation and commissioning on site.
Key Facts
• Safety PLC: Allen Bradley Compact GuardLogix 5380 (5069-L306ERS2), rated SIL2 / Performance Level d
• Safety I/O: 2× POINT Guard 8-point safety input modules (1734-IB8S) and 1× POINT Guard 8-point safety output module (1734-OB8S)
• System controls movement of a scissor lift platform and access door, interlocked against two access gates
• Separate stainless steel pushbutton station provided alongside the main IP66 control panel
• Allen Bradley 7-inch HMI (2713P-T7WD1) included
• 4× safety-rated gate/door interlock switches (2× Guardmaster side-actuated, 2× telescopic-arm actuated)
• Software written in Allen Bradley Studio 5000; BS EN 13849 performance level assessment provided
• CE Declaration of Conformity issued; FAT schedule and certificate provided
• Installation and commissioning included