How to maintain the grid-connected cabinet under normal conditions?

1. Daily inspection (recommended frequency: once a week, with additional inspection after extreme weather)

1. Appearance and environmental inspection
cabinet status: Check the shell for deformation, rust, and damage, ensure the cabinet door is tightly sealed, and assess the flexibility of the lock to prevent dust/moisture intrusion. For outdoor models, focus on inspecting the waterproof seals to avoid water leakage and condensation
Identification specifications: Confirm that the equipment name, number, and warning signs (such as "Danger High Voltage") are clear and complete, and that the wiring terminal labels are not detached
Environmental requirements: Keep the area within 0.8 meters around the cabinet clear of debris and flammable materials, and ensure good ventilation. Maintain the environmental temperature between -10℃ and 40℃, with humidity no higher than 90% (at 25℃). Avoid direct sunlight or exposure to enclosed, hot and stuffy environments
2. Operational status monitoring
Instruments and indicator lights: Observe whether parameters such as voltage, current, and power are within the rated range, and whether the color/flashing status of the indicator lights conforms to the equipment manual (e.g., the power light is constantly on, and the fault light is off)
Abnormality identification: Monitor for any abnormal noises such as buzzing or crackling, and check the cabinet shell for any abnormal heating (normal temperature rise ≤70℃), pungent odor, or smoking
Grounding and Insulation: Visually inspect the grounding wire for secure connection, and ensure that insulating components (such as insulators and bushings) show no signs of aging, cracking, or carbonization
II. Regular maintenance (core cycle: half a year/1 year, adjusted according to environmental intensity)
1. Cleaning and fastening (once every six months)
Cleaning operation: Use a dry soft cloth or a brush to remove dust from inside the cabinet, with a focus on cleaning the cooling vents, the surfaces of electrical components, and the busbar connections. It is strictly prohibited to use wet cloths or corrosive cleaning agents. The cooling fan blades need to be cleaned of dust, and the filter screen should be replaced regularly
Tightness inspection: Use a torque wrench to tighten all wiring terminals, busbars, and cable connectors to the standard torque (25-35N·m for busbar bolts below 1600A) to prevent loosening and heating caused by vibration. Check the bolts for rust, and replace the anti-loose components if necessary
2. Component inspection and maintenance (once a year)
Electrical components: Inspect the contact wear of components such as Circuit Breakers, contactors, and relays, and replace aged/eroded components; ensure that fuses and capacitors are intact and free from bulging or leakage
Mechanical lubrication: Apply specialized lubricant (such as silicone-based grease) to moving parts such as circuit breaker operating mechanisms and switch handles to ensure smooth and unimpeded operation
Protection device verification: Test the accuracy of the overload, short circuit, and leakage protection functions, and verify whether the protection settings meet the grid requirements; simulate and test the reliability of automatic switching devices and backup power supplies
3. Special inspection (once a year, combined with intelligent tools)
Insulation test: Measure the insulation resistance of the main circuit with a 2500V megohmmeter (≥10MΩ), and the secondary circuit with a 500V megohmmeter (≥1MΩ). Before testing, disconnect the electronic equipment and fully discharge it
Temperature monitoring: Use an infrared thermal imager to inspect critical components such as busbar connectors and cable terminations, identifying any latent hot spots (those with a temperature difference exceeding 10°C require special attention)
Lightning protection and surge protection: Check the status indicator lights of SPD (surge protector), replace failed modules before thunderstorm season, and ensure that the grounding resistance meets the requirements (generally ≤4Ω)
III. Emergency Handling of Common Faults
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Fault type
Typical manifestation
Handling measures
Frequent tripping
The protective device repeatedly operates
1. Check whether the load is overloaded or short-circuited, and inspect the insulation of the circuit; verify the protection setting values to avoid setting the sensitivity too high; >3. Do not reset blindly, and only restore power supply after the fault has been eliminated
Abnormal fever
Local temperature rise of the cabinet exceeds the standard
1. Secure loose connectors and clean the cooling channels; 2. Inspect the oxidation of contact points, polish them, and reconnect; if components are aged, replace them immediately
Insulation fault
Insulation resistance decreases and leakage current increases
1. Inspect components affected by moisture during power outages and replace aged insulating parts; 2. Clean dirt from insulating surfaces and reapply insulation treatment; operation can only be resumed after passing the test
Communication failure
Data not updating, display screen black
1. Check the power supply and network connection, and restart the device; 2. Contact the manufacturer to upgrade the firmware or replace the communication module; 3. Ensure reliable wiring between the monitoring system and the cabinet
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IV. Safety operation specifications
Personnel qualifications: Maintenance personnel must hold relevant certificates, be familiar with equipment structure and operating procedures, and wear protective gear such as insulating gloves and shoes
Power outage procedure: Strictly follow the procedure of "power outage - electricity inspection - hanging grounding wire - setting up warning signs". Capacitive equipment needs to be discharged for more than 5 minutes
Prohibited behaviors: Unauthorized modification of protection settings and removal of interlocking devices are strictly prohibited; live-line work must be supervised by two people, maintaining a safe distance (≥0.7 meters for 10kV systems)
Fire protection preparations: Equip dry powder fire extinguishers near the cabinet (regularly inspected according to GA95 standards), and strictly prohibit stacking flammable materials
V. Maintain archive management
Establish equipment ledgers to record installation dates, model parameters, previous maintenance records (time, content, personnel), and details of fault handling
Classified and archived inspection reports (insulation testing, temperature monitoring data), along with component replacement vouchers, facilitate the tracing of equipment lifecycle status
Annually summarize maintenance data, analyze failure patterns, and optimize maintenance cycles (for example, shorten the cleaning cycle to three months in dusty environments)