继电器由磁路部分和接点部分两大部分构成。其工作原理是通过继电器线圈中的电流在电磁铁中产生的吸力驱使衔铁及可动部分动作，来改变接点系统的工作状态。其特征是动作可靠、准确，使用寿命长，有足够的闭合和断开电路的能力，有较高的绝缘强度，稳定的时间和电气参数。 

The relay consists of a magnetic circuit part and a contact part. Its working principle is to change the working state of the contact system by the action of armature and movable part driven by the current in the relay coil in electromagnet. It is characterized by reliable and accurate operation, long service life, sufficient ability to close and disconnect circuits, high insulation strength, stable time and electrical parameters.