Grosvenor Mine: Shaft 4&5 Surface Exhaust Fan Control System
The Challenge
Grosvenor Mine required a new interim ventilation system for Shaft 4 and 5 to support re-entry into underground workings. The challenge was significant: the site needed to repurpose an existing goaf dewatering package and integrate it into a 1MW, 3.3kV exhaust fan system while layering in comprehensive instrumentation, gas monitoring, and remote control capabilities that could operate safely from the site’s central SCADA platform.
Our Approach
Deftec designed and delivered a complete PLC control system built on Allen-Bradley ControlLogix architecture, handling all instrumentation integration, logic programming, and hardware configuration. The solution encompassed a refurbished switchroom with an ACS1000 variable speed drive controlling the fan motor, paired with real-time monitoring of airflow, static pressure, and gas composition across two shaft ducts. We integrated dual knife gate valves with remote and local control modes, a motor-actuated damper system, and a four-level gas panel monitoring CH4, CO, O2, and CO2 levels. The system was designed with multiple operational modes — automatic remote operation via SCADA, local control from the switchroom panel, and critical safety interlocking tied to the site’s underground intertrip system. All electrical termination, testing, and commissioning took place on-site between May and July 2025.
The Outcome
The system was successfully commissioned and handed over to Anglo American, enabling safe, remotely monitored ventilation for mine re-entry operations. Grosvenor Mine now has a flexible, redundant control architecture supporting both autonomous operation and hands-on local management, with full alarm and trip functionality integrated into the existing site SCADA infrastructure. The solution demonstrates Deftec’s capability to retrofit and upgrade critical infrastructure in active mining environments while maintaining safety-critical performance standards.
Technologies and Capabilities
- Allen-Bradley ControlLogix PLC programming and configuration
- ACS1000 variable speed drive integration and tuning
- SCADA system integration and remote monitoring
- 4-20mA instrumentation (airflow, pressure, gas transmitters)
- High-voltage switchgear and protection relay coordination
- Emergency stop and safety interlock logic
- Knife gate and damper valve automation
- Multi-mode control systems (automatic/local/disabled)
- On-site factory acceptance testing (FAT) and site acceptance testing (SAT)
- ITP/ITR documentation and handover support