Core insulation method and process analysis of compact medium voltage cabinet Electrical Copper BusBar

Heat shrink tubing wrapping is a classic way of insulation treatment for Electrical Copper BusBar, which is suitable for the basic insulation requirements of medium and low voltage compact switchgear, and has both convenient operation and cost advantages. The core advantage of this method is that it can effectively reduce the electrical gap between copper bars, significantly reduce the size of the switchgear cabinet, and the heat shrinkable sleeve can withstand a temperature of up to 125 ℃. As long as the operating temperature rise of the copper bars is within a reasonable range, the sleeve can be used stably for a long time without insulation layer damage. In practical applications, the insulation performance of high-quality heat shrink tubing is excellent. For example, when dealing with 75kV impulse withstand voltage at 12kV level, it only needs to ensure that the air clearance between the Ground Bus Bar is greater than 65mm to meet the insulation requirements. This technology has also been applied in many mainstream compact switchgear, achieving reasonable compression of cabinet phase spacing and efficient utilization of space.

Epoxy vulcanization coating is a more efficient Electrical Copper BusBar insulation method than heat shrink tubing coating, especially suitable for compact switchgear with high voltage levels such as 40.5kV. It can significantly reduce the insulation distance between copper bars and relative ground, while reducing the volume of the cabinet, greatly improving the overall insulation quality and operational reliability of the switchgear. The basic process of epoxy vulcanization coating requires cutting, bending, stamping and other forming processing of the Electrical Bus Bar, followed by insulation treatment using professional powder coating technology; The epoxy resin powder used is a thermosetting coating, which is made by mixing synthetic resin with curing agents, modifiers and other raw materials through hot melting, cooling, crushing and screening. It can be applied to the surface of copper bars through various methods such as vulcanization bed, electrostatic spraying, thermal spraying, and hot-dip coating, and has insulation, anti-corrosion and decorative functions.

The epoxy resin coating formed by epoxy vulcanization coating adds excellent alkali resistance, heat resistance, corrosion resistance, and electrical insulation to BusBar Copper while retaining its original high strength, high stiffness, low resistance, and high current transmission characteristics, greatly extending the service life of copper bars in switchgear. Its insulation performance is particularly outstanding, with a theoretical breakdown strength greater than 52kV/mm and an actual allowable strength of 30-35kV/mm. In engineering applications, it is required that the thickness of the epoxy resin coating on the surface of the copper bar be no less than 2mm.

The reliability of this insulation method was also verified by relevant high-voltage tests: two Bus Bar Electric crosses coated with 2mm thick epoxy resin can withstand 50kV power frequency voltage for 1 minute at a 30mm clean air distance; Even with a clean air distance of 0mm, it can still withstand a 50kV power frequency voltage for 1 minute with only slight discharge sound; The High Voltage BusBar coated with epoxy resin crosses with bare copper bars, and can withstand 30kV power frequency voltage for 1 minute at a clear air distance of 30mm, with obvious discharge sound. This further illustrates the key role of epoxy vulcanization coating in the insulation protection of copper bars, and also reflects the need to maintain a larger electrical clearance when using bare copper bars and insulated copper bars in the same cabinet.

In the industry application of BusBar Voltage insulation technology, epoxy vulcanization coating has become the preferred solution for high-voltage switchgear due to its excellent insulation and weather resistance. The IEEE C37.20.2 standard specifies that Power Bar BusBar in relevant scenarios must be treated with epoxy vulcanization insulation and pass the flame retardant test required by the standard to ensure the safe operation of the switchgear. The heat shrink sleeve coating is widely used in compact medium and low voltage switchgear due to its advantages of a simple process and controllable cost. The reasonable selection of two processes needs to be comprehensively considered based on factors such as the voltage level of the switchgear, the compactness requirements of the cabinet, the structure and shape of the High Current Contacts, and the engineering cost, in order to achieve the optimal match between insulation performance and equipment economy.

The selection of Electrical Copper BusBar insulation technology needs to be comprehensively considered based on the voltage level and compactness requirements of the switchgear, in order to achieve the optimal match between performance and economy. If you have any related needs for copper bar insulation process selection and customization, please feel free to contact us at any time to provide you with professional technical support and solutions.