Preventive maintenance can reveal heat, contamination, vibration, loose connections, ageing fans, and failing power supplies before they cause an unplanned shutdown. Work must follow site safety rules and be performed by qualified personnel.
Before opening the panel
Review drawings, permits, lockout procedures, arc-flash requirements, and the panel history. Never bypass interlocks or protective devices to complete an inspection.
Visual and environmental checks
- Door seals, filters, fans, vents, and cabinet temperature
- Dust, moisture, oil, corrosion, pests, and blocked airflow
- Discoloration, melted insulation, unusual odor, or vibration
- Loose ducts, unsupported cables, and damaged glands
Electrical and control checks
Where approved procedures permit, inspect terminals, protective devices, contactors, relays, power supplies, UPS units, batteries, grounding, and network connections. Use thermography or measurements only with appropriate training and equipment.
Protect programs and records
Maintain current PLC, HMI, drive, and safety-controller backups. Record firmware, software versions, network settings, replacement history, and critical spare part numbers. Label changes on the drawings.
After maintenance
Remove tools and debris, restore covers, verify protective earth and door bonding, close the panel correctly, and test operation according to the approved commissioning procedure.
For replacement components, send US² Automation the manufacturer, complete part number, quantity, panel voltage, and application details.