NMDC OCSL Upgrade
Upgrading NMDC's OCSL Plant — Zero Downtime
Design, engineering, and commissioning of a redundant Siemens PLC and Remote I/O upgrade at NMDC's Ore Crushing and Screening Line, Kirandul — with production never stopping.
At a Glance
- Zero production downtime during migration
- Siemens S7-1512 & S7-1215 PLCs, redundant power modules
- Dual 10 KVA UPS with automatic switchover
- Fully redundant Ethernet backbone
- Historian-based SCADA, 30-day alarm retention
Background
NMDC's Ore Crushing and Screening Line (OCSL) plays a mission-critical role in the company's iron ore production chain. The existing PLC panels and control systems, after decades of continuous use, had reached obsolescence — posing risks of failure and reduced operational efficiency. The modernization was designed around a single principle: minimum downtime, allowing a smooth transition to the latest control platform while plant operations continued uninterrupted.
What We Delivered
The upgraded system is built on a distributed architecture using advanced Siemens PLCs and modular Remote I/O panels, interfaced through a high-speed, redundant Ethernet backbone for real-time control and seamless communication between every automation node. Logic transfer and communication migration were performed online — the plant never stopped running. Local HMIs were installed on every RIO panel for real-time field-level monitoring, and engineering/monitoring workstations were connected via an optical fibre backbone for unified remote access.
Results
The legacy system was fully replaced with a Siemens-based redundant PLC platform without a single process stoppage — boosting reliability, efficiency, and processing performance. Conveyor braking and local control loops were integrated into one unified system, a fully functional centralized SCADA platform with remote diagnostics was commissioned, and the spare-capacity hardware strategy leaves room for future expansion without planned shutdowns.
