A DC fast charger is a power unit subjected to intensive use and, often, to outdoor conditions. Preventive maintenance isn't an optional expense — it's what keeps a minor fault from turning into a long, costly outage.
On the electrical side, it's worth periodically checking the condition of power connectors and cables (wear, overheating at contact points), the tightness of internal connections, and the proper functioning of the residual current and circuit-breaker protections.
On the mechanical and environmental side, check the condition of the seals and closures that maintain the IP protection rating, the cleanliness of the ventilation or cooling systems, and the physical condition of the touchscreen and LED indicators.
On the software side, updating the charger's firmware and verifying that connectivity (WiFi, Ethernet, or 4G) and OCPP communication with the management platform are still working correctly prevents a charger from "working" electrically while remaining invisible to remote management.
An annual preventive maintenance plan with documented inspections doesn't just extend the equipment's service life — in many cases it's also a requirement for keeping the manufacturer's warranty valid and for justifying the proper use of any grants or subsidies received.