single transformer can be divided into three-phase transformers and single phase transformer

oil immersed distribution transformers 1000kVA and above, shall be installed outdoor thermometer type signal, and then the distant signal. 800kVA and above should be installed oil immersed distribution transformer gas relay and pressure protection device, 800kVA transformer oil-immersed according to the following requirements, in consultation with the manufacturer, but also can be equipped with gas relay. Dry-type transformers shall be specified by the manufacturer, the installation of a temperature measuring device, and more generally for the 630kVA transformer installations.
Products classified according to the number of phases to distinguish between single transformer can be divided into three-phase transformers and single phase transformer

. In a three-phase power system, the general application of the three-phase transformer, when the oversized transport conditions and subject to the  three single-phase power system can also be applied consisting of three single-phase transformer transformer group.