Protection & Arc Flash Studies — Geological Stabilisation Equipment

Overview

A Bowen Basin coal mine was facing difficult geological conditions that had halted longwall mining operations. To stabilise the ground and allow safe recommencement of longwall production, specialist equipment was brought in — equipment that had to be energised and operated in a challenging underground environment under strict safety requirements.

Before the equipment could be put into service, the mine needed to verify that its electrical protection systems were correctly configured and that arc flash risks had been properly assessed. Grid Dynamics was engaged to carry out the protection studies and arc flash assessments required to safely energise and operate the equipment.

The stakes were high: the equipment was critical to getting longwall production restarted, and any delay had direct operational and commercial consequences for the mine.

Scope of Work

• Protection coordination study for the electrical systems feeding the geological stabilisation equipment, verifying correct fault clearance and selectivity
• Review of protection relay settings against system fault levels and equipment characteristics
• Arc flash assessment for the relevant switchgear and distribution equipment, determining incident energy levels and establishing arc flash boundaries
• Identification of any gaps in protection coverage or settings requiring modification
• Preparation of engineering reports documenting findings and recommendations, suitable for use by the mine’s electrical engineering team and regulatory requirements

Outcome

The protection studies confirmed the adequacy of the protection arrangements for the stabilisation equipment, with any required modifications to relay settings identified and documented. The arc flash assessment established the safe working boundaries and personal protective equipment requirements for personnel working on or near the energised equipment.

With the engineering completed and documented, the equipment was safely energised and the geological stabilisation programme proceeded. Longwall mining was able to recommence, achieving the operational outcome the mine required.