该变压器在SG变压器上面安装一个外壳，起到有效的保护变压器，安全美观的同时也提升了变压器的档次，外壳的安装方式有很多种，可以是就罩在变压器上面的，也可以是整个变压器放在壳子里面的，四周都是与外壳绝缘的，在外壳边上开孔，方便接线的引入，并在外壳表面开一扇可以打开的门，方便接线，在外壳上安装散热风扇等等。

       SG（ZSG）系列三相干式变压器广泛应用于工矿企业、数控机床、加工中心、自动化控制设备，各类机械、发电厂、机场、高层建筑、地铁等安全防火要求较高的场所。作变换电压，供照明电器设施，数控系统，动力电源、整流电源之用。该产品是户内装置，空气自冷或风冷式。
 
         SG(ZSG) series three-phase dry-type transformers are widely used for industrial and mining enterprises，NC machine tools，processing centers，automatic controlling equipments，various kinds of machineries and places with stricter requirements for security and fireproofing，such as power plants，airports，high-rise buildings and subways etc.，serving as voltage transformer，power supply for lighting apparatus and facilities，numerical control systems，dynamical powers and rectifier powers.The products are indoor equipments，which are self-cooling by air or wind cooling.