Anglo American Grosvenor Mine: MG103 Ventilation Fan Control System

The Challenge

Anglo American’s Grosvenor Mine required a new surface ventilation system to manage additional airflow during longwall mining operations. The MG103 ventilation fan installation demanded comprehensive electrical and control system design — including a 2MVA transformer kiosk feeding the fan motor, integration with underground mine safety systems (methane and pressure monitoring), and safe operator interface that kept personnel outside high arc flash risk zones.

Our Approach

Deftec, working within Anglo American’s Major Electrical team, designed a dual-layer PLC control architecture to address both safety and operational requirements. The primary control logic ran on a Control Logix processor housed in the transformer kiosk, managing high-voltage switching and motor coordination. A remote Flex I/O-based operator panel was positioned outside the arc flash boundary, allowing safe manual control via pushbuttons and a Citect HMI display, with redundant pushbutton control if the display failed. The system integrated an Ampcontrol Gasguard intrinsically safe gas monitoring controller to monitor methane, CO, and oxygen levels, with trip logic coordinated through the PLC to remove underground power when gas levels exceeded site limits. Detailed functional specifications confirmed all intertrips: loss of main ventilation fans, collar pressure anomalies, and emergency stop chains across multiple site locations.

The Outcome

The control system was successfully commissioned in 2020 with comprehensive wet commissioning protocols verifying all underground power intertrip scenarios, gas detection trips, and emergency stop functionality. The architecture ensured operator safety by eliminating manual switching in high arc flash zones, while the integrated gas monitoring and mine ventilation intertrips provided critical protection for underground personnel. The system provided Anglo American with a reliable, compliant ventilation asset that managed both surface cooling requirements and mine-wide safety protocols.

Technologies and Capabilities

• PLC Programming: Control Logix and Flex I/O platforms (Allen-Bradley)
• SCADA & HMI: Citect display and B&R industrial PC for operator interface
• Gas Monitoring: Ampcontrol Gasguard intrinsically safe gas controller (Ex ia rated, Zone 0 hazardous area)
• High Voltage Switching: 2MVA transformer kiosk control with dual switchgear management (ring isolators, circuit breakers, earth switches)
• Electrical Safety: Arc flash risk assessment, AS2067 compliance, emergency lighting and egress design
• Intertrip Logic: Underground power coordination with main ventilation systems, pressure and gas-based trip functions
• Commissioning: Functional and wet commissioning protocols across distributed mine sites