Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

1.Transformer Maintenance and Inspection Open the low-voltage (LV) circuit breaker of the transformer under maintenance, remove the control power fuse, and hang a “Do Not Close” warning sign on the switch handle. Open the high-voltage (HV) circuit breaker of the transformer under maintenance, close the grounding switch, fully discharge the transformer, lock the HV switchgear, and hang a “Do Not Close” warning sign on the switch handle. For dry-type transformer maintenance: first clean the porcel

In practical work, insulation resistance of distribution transformers is generally measured twice: the insulation resistance between thehigh-voltage (HV) windingand thelow-voltage (LV) winding plus the transformer tank, and the insulation resistance between theLV windingand theHV winding plus the transformer tank.If both measurements yield acceptable values, it indicates that the insulation among the HV winding, LV winding, and transformer tank is qualified. If either measurement fails, pairwise

Design Principles for Pole-Mounted Distribution Transformers(1) Location and Layout PrinciplesPole-mounted transformer platforms should be located near the load center or close to critical loads, following the principle of “small capacity, multiple locations” to facilitate equipment replacement and maintenance. For residential power supply, three-phase transformers may be installed nearby based on current demand and future growth projections.(2) Capacity Selection for Three-Phase Pole-Mounted Tr

1.Noise Mitigation for Ground-Level Independent Transformer RoomsMitigation Strategy:First, conduct a power-off inspection and maintenance of the transformer, including replacing aged insulating oil, checking and tightening all fasteners, and cleaning dust from the unit.Second, reinforce the transformer foundation or install vibration isolation devices—such as rubber pads or spring isolators—selected based on the severity of vibration.Finally, strengthen sound insulation at weak points of the ro

1.Electric Shock Risk Prevention and ControlAccording to typical design standards for distribution network upgrades, the distance between the transformer’s drop-out fuse and the high-voltage terminal is 1.5 meters. If a crane is used for replacement, it is often impossible to maintain the required minimum safety clearance of 2 meters between the crane boom, lifting gear, slings, wire ropes, and the 10 kV live parts, posing a severe risk of electric shock.Control Measures:Measure 1:De-energize th

1. General Requirements for Pole-Mounted Transformer Platforms Location Selection:Pole-mounted transformers should be installed near the load center to minimize power losses and voltage drop in low-voltage distribution lines. Typically, they are placed close to facilities with high electricity demand, while ensuring that the voltage drop at the farthest connected equipment remains within allowable limits. The installation site should allow easy access for maintenance and avoid complex pole struc

Rockwill Electric Co., Ltd. has successfully passed the real-scenario single-phase-to-ground fault test conducted by the Wenzhou of China Electric Power Research Institute for its DA-F200-302 hood-type feeder terminal and integrated primary-secondary pole-mounted circuit breakers—ZW20-12/T630-20 and ZW68-12/T630-20—receiving an official qualified test report. This achievement marks Rockwill Electric as a leader in single-phase ground fault detection technology within distribution networks.The DA

Common Faults and Causes in Routine Inspection of Distribution TransformersAs the terminal component of power transmission and distribution systems, distribution transformers play a critical role in supplying reliable electricity to end users. However, many users have limited knowledge of power equipment, and routine maintenance is often carried out without professional support. If any of the following conditions are observed during transformer operation, immediate action should be taken: Excess

The Battambang Conch PV + Energy Storage Power Station in Cambodia has successfully completed its grid-connected trial operation. The project utilized medium-voltage switchgear supplied by Rockwill Intelligent Electric Co., Ltd. Despite numerous challenges—including an extremely tight delivery schedule—Rockwill Intelligent delivered high-quality products and exceptional service throughout project execution, earning consistent praise from the client.Located in Battambang, Cambodia, the Battambang

Analysis of Lightning Protection Measures for Distribution TransformersTo prevent lightning surge intrusion and ensure the safe operation of distribution transformers, this paper presents applicable lightning protection measures that can effectively enhance their lightning withstand capability.1. Lightning Protection Measures for Distribution Transformers1.1 Install surge arresters on the high-voltage (HV) side of the distribution transformer.According to SDJ7–79 Technical Code for Overvol