Recently, DC microgrids have become a viable option for mining distribution systems. Fault diagnostics and protection are known challenges in DC microgrids. In this paper, we present an overview of the existing strategies for fault diagnostics and protection of a DC microgrid and apply them to an open cut DC mine scenario, which includes large electric excavators. We propose a comprehensive fault tolerance strategy based on analysis of electrical and mechanical operations of an electric rope shovel and identification of its working cycle. Based on this strategy, in case of a fault, the electric rope shovel will be able to perform required actions to avoid collisions and safely finish its working cycle, while maintaining electric safety.