Setting up an interlocking is a complex process that requires careful planning, design, installation, testing, and commissioning. The first step is to design the interlocking layout based on the track configuration, signal locations, switch locations, and operating requirements.
The design process often includes detailed drawings, route charts, control tables, software logic, and simulations. These documents help verify that the interlocking will safely control train movements before any field equipment is placed into service.
Once the design is approved, the physical installation begins. This includes installing switches, switch machines, signals, track circuits, cables, power equipment, cases, houses, and communication equipment needed for the interlocking system.
Proper alignment, wiring, grounding, bonding, and equipment placement are critical. Each piece of equipment must be installed correctly so the interlocking logic can safely monitor and control the field devices.
After installation, thorough testing and commissioning are required. This includes verifying switch correspondence, signal indications, route locking, approach locking, traffic locking, track occupancy, and interlocking logic.
Testing must confirm that conflicting routes cannot be established and that trains can only be authorized through safe routes. Once testing is complete and all issues are corrected, the interlocking can be placed into service.
After being placed in service, regular maintenance and inspections are needed to ensure continued reliability and safety. This includes equipment checks, periodic tests, inspections, software reviews, and documentation updates.