1. A certain amount of time is required for a thermal relay to reset after tripping; automatic resetting should occur within 5 minutes, while for manual resetting, the reset button should not be pressed until 2 minutes have elapsed.
2. Following a short-circuit fault, inspect the heating elements and bimetallic strips for deformation; if any abnormalities are found, adjust them promptly without removing the components.
3. Thermal relays in service should be inspected weekly. Checks should cover: signs of overheating, unusual odors, or electrical discharge; loose, detached, or poorly connected screws; and the condition of the casing (checking for damage and cleanliness).
4. Thermal relays in service should undergo a comprehensive overhaul annually. This includes: cleaning, inspecting and repairing components, verifying that insulation resistance exceeds 1 MΩ, and performing functional testing under power. Once calibrated, do not tamper with any screws other than the terminal screws.
5. When replacing a thermal relay, the new unit must comply with the original specifications and requirements.
6. Periodically check all wiring connections for looseness; never bend the bimetallic strip during maintenance or inspection.
