Designed and built by Eaton in accordance with IEC 62271 specifications, the Power Xpert UX medium voltage air insulated switchgear system features the latest in withdrawable vacuum circuit-breakers. The complete system is made up of three product lines UX12, UX17 and UX24 for use on supply voltages of 12, 17.5 kV and 24 kV. It is designed to be used in indoor withdrawable primary switchgear applications, such as distribution substations and main stations and as a connection to industrial and energy providers. The system uses an environmentally friendly vacuum technology in conjunction with solid and air insulation, providing a conservational alternative to switchgear systems using sulfur hexafluoride (SF6) gas. It offers the benefits of simple cable connection, compactness, operational reliability and user-friendliness with a single busbar system. The system comes in a range of designs up to 4000 A and with a rated short-time withstand current up to 50 kA for 3s at 17.5 kV and 25 kA for 3 seconds at 24 kV. Panel widths are only 600 mm for up to 1250 A, 800 mm for up to 2000 A and 1000 mm for up to 4000 A. The vacuum circuit breakers at the heart of the system are designed and built to the IEC 62271-100 standard. The UX has been designed to prevent the initiation of an internal arc under normal operation and maintenance. However, in the unlikely event of an open arc occurring, it has been fully tested to provide IAC ratings of 25 kA for 1s; 31.5 kA for 1s, 40 kA for 1s and 50 kA for 0.5s depending on the specific rating and configuration. Tested to provide safety to personnel at the front, sides and rear of the switchgear the system provides the highest degree of safety for personnel as defined in the IEC standard of AFLR. The system provides the highest level of operational continuity with four segregated earthed metal compartments provided for low voltage control and protection; busbar chamber; vacuum circuit breaker compartment; cable compartment. The design provides the highest degree of loss of service continuity as defined in the IEC standard or LSC-2B PM. It can be customized to meet specific customer protection and control requirements with a range of digital systems for protection and remote control. All these features ensure that the system is ideally suited for use in current and such future electrical networks as smart grids. Some of the application areas include power distribution, water and waste water treatment, mining, commercial buildings, industrial facilities, oil and gas (on and offshore), marine, as well as airports and hospitals.
Edited by: Teoman Tugsuz
