After the start of the fu period, sustained high temperatures prevail across many regions nationwide. Power consumption loads rise simultaneously in industrial plants, data centers, commercial buildings and other sites, making electrical equipment prone to faults all year round. High temperatures intensify conductor heat generation, accelerate insulation aging and loosen electrical connections. Insufficient operation and maintenance management can easily lead to excessive temperature rise, insulation breakdown and even electrical fires.

 Based on current standards including GB 7251, GB 50150 and GB 50054, this paper focuses on two core pieces of equipment – busway and power distribution cabinet. It sorts out key inspection points, standardized operating procedures and hidden danger disposal solutions for summer operation and maintenance, providing professional guidance for power safety in various scenarios.

一、Core Risks Under High-Temperature Operating Conditions

 Current-carrying capacity derating & accumulated temperature rise: For every 5°C rise in ambient temperature, the equipment’s current-carrying capacity drops by 5%~8%. Long-term full-load operation tends to exceed the national standard limit for temperature rise.

Insulation aging & higher breakdown risk: High temperatures accelerate thermal cracking of organic insulating materials. Combined with humidity and dust, this may easily cause tracking discharge and insulation breakdown.

Relaxed connection stress & vicious cycle of joint overheating: Thermal expansion and contraction aggravate bolt loosening, which continuously increases contact resistance and worsens heat generation step by step.

散热通道堵塞，内部积热：粉尘油污堵塞散热路径，高温下散热效率进一步下降。 Blocked heat dissipation passages & internal heat accumulation: Dust and oil stains block heat dissipation paths, further reducing heat dissipation efficiency under high temperatures.

二、 Core Points for Summer Operation & Maintenance of busway

 As the core component for high-current power transmission and distribution, busways are highly susceptible to temperature rise faults in summer. Closed-loop management covering the full process of inspection, maintenance and fault disposal shall be implemented.

1.  Routine Inspection: Increase Inspection Frequency & Focus on High-Risk Points

During peak power consumption periods, general sites shall be inspected no less than twice a week, and critical load equipment once daily. Temperature measurement shall be conducted more frequently during peak hours.

Infrared temperature measurement (core procedure): Focus on connecting joints, plug-in units, corner/reducer sections and enclosed shaft sections. Per GB 7251.2, the allowable temperature rise limit for conductors is 70K. Any temperature difference over 15K between adjacent points on the same circuit shall be closely monitored. Establish a temperature measurement log to record ambient temperature and load current synchronously for longitudinal trend comparison.

Visual & environmental inspection: Check the integrity of cabinet sealing and wall penetration sealing, whether ventilation passages are blocked, and detect abnormal electromagnetic noise or burnt odor.

Structural & earthing inspection: Ensure no jamming on support hangers and expansion joints, and continuous, reliable connection of main earthing conductors.

2. Periodic Maintenance: Complete Closed-Loop Maintenance Before High-Temperature Season, Conduct Supplementary Monthly Verification

Thoroughly remove dust and oil accumulated on cabinets and heat dissipation gaps to ensure unobstructed heat dissipation.

After power cut, retighten all terminal bolts in accordance with the manufacturer’s standard torque to compensate for stress relaxation caused by thermal expansion and contraction.

Test inter-phase and phase-to-earth insulation resistance with a 1000V megohmmeter. The insulation resistance of low-voltage busways shall be no less than 0.5MΩ. If the reading is low, troubleshoot dampness and insulation aging issues.

3. Standard Disposal of Common Hidden Dangers

Excessively high joint temperature rise: Immediately reduce load if caused by overload. For poor contact, cut off power, polish contact surfaces, apply conductive grease, retighten bolts to specified torque, and restore power only after passing re-inspection. Install mechanical ventilation for enclosed installation scenarios.

Low insulation resistance: Check for water ingress and condensation, and ventilate to dry the equipment. Replace damaged or aged insulation layers promptly; operation with hidden dangers is strictly prohibited.

Overheating plug-in units: Inspect plug-in claws for deformation and oxidation. Conduct minor polishing for slight defects, and replace severely damaged components to guarantee full insertion and reliable locking.

Mega Technology Optimus PRO Series epoxy cast busways and fluidized insulated busways adopt integrated insulation molding technology. The insulation layer is seamlessly bonded with high-purity oxygen-free copper conductors, achieving a Class H temperature resistance rating (180°C) for superior current-carrying stability under high temperatures. Its dense structure delivers outstanding moisture-proof, dust-proof and anti-corrosion performance, effectively preventing insulation aging and breakdown caused by hot and humid summer conditions. The low-impedance conductor design generates lower operating temperature rise and requires zero maintenance for long-term operation, greatly reducing summer operation and maintenance workload.

三、Core Points for Summer Operation & Maintenance of Low-Voltage Power Distribution Cabinets

1. Routine Inspection

Maintain the power distribution room ambient temperature between 5°C and 40°C with humidity ≤75%, and ensure air conditioning, ventilation and dehumidification equipment operate normally.

 Monitor current and voltage of each circuit, and keep the three-phase load unbalance degree within 10%. Check circuit breakers and contactors for abnormal noise, peculiar smell or discoloration.

For capacitor compensation cabinets, focus on checking capacitors for bulging and liquid leakage, and reactors for overheating.

2.Periodic Maintenance

Cut off power and clean dust and debris inside cabinets to keep heat dissipation air ducts unobstructed.

Recheck fasteners for main circuits and secondary terminals to eliminate loosening risks from thermal expansion and contraction.

 Calibrate protection setting values and functions to match actual loads, preventing false tripping or failure to trip under high temperatures.

3. Hidden Danger Disposal

In case of component overheating, capacitor bulging, three-phase load imbalance and other faults, reduce the load or cut off power immediately for component replacement or load adjustment. Operation with faults is strictly forbidden.

四、General Safety Specifications & Long-Term Optimization Suggestions

1. Bottom Line for Operation Safety

For power-off maintenance, strictly implement the "power cut, voltage test, earthing, warning tag posting, lockout" procedure, which shall only be performed by certified electricians. Wear full protective gear during live-line inspection under high temperatures, and never touch hot live components.

2. Load & Emergency Handling Principles

Avoid full-load operation of equipment during hot weather; unauthorized capacity expansion is prohibited. Reduce load or cut off power immediately once abnormalities are detected, and restore power only after faults are eliminated and re-inspection passes. Keep complete operation and maintenance records to form a closed loop of inspection, rectification and recheck.

3. 长效选型优化 Long-Term Equipment Selection Optimization

Reduce summer maintenance pressure from the source: Prioritize epoxy cast /fluidized insulated busways with excellent temperature resistance and protection for high-temperature, high-humidity and dusty sites. Reserve sufficient capacity derating margin for enclosed installation under heavy loads. Equip critical loads with intelligent monitoring devices to shift from passive fault disposal to active prevention.

All power distribution products of Mega Technology Optimus PRO Series adopt internal quality control standards stricter than national specifications, suitable for various complex high-temperature working conditions. Supported by a comprehensive technical service system, we provide full-process project support covering model selection, design, delivery and operation & maintenance guidance.

If you require services including summer hidden danger inspection of power distribution systems, equipment upgrading & renovation, or operation & maintenance technical consultation, please send a private message to our backend to arrange professional technical support.