本标准规定了电力变压器的绝缘水平和介电测试要求，其中:（1）变压器绝缘水平和介电测试要求符合本标准。1（2）变压器的最高电压绕组为Y形连接，额定电压为345 kV或以上。（3） 变压器拟在有效接地系统2上运行，并由合适的电涌放电器保护。

This standard prescribes insulation levels and dielectric test requirements for power transformers where: (1) The transformer insulation levels and dielectric test requirements are specified to be in accordance with this standard.1 (2) The highest voltage winding of the transformer is wye connected and rated 345 kV or above. (3) The transformer is intended for operation on an effectively grounded system2 and is protected by suitable surge arresters.