1用户安装的电能表容量与用户的负荷大小相差很大,使电能表中的电流过大而烧毁。2电能表的下线引出处闪烁电火花,主要是因固定螺丝松动、生锈,造成接触不良引起局部过热而打火。3用户的导线选择不当,线径与电器设备的工作电流相差太大,或导线的质量不合格,加上走线集中并扎在一 1 user-installed watt-hour meter capacity and the size of the user’s load varies greatly, so that the current meter is too large and burned. 2 watt-hour meter out of lead flashing sparks, mainly due to loose screws, rusty, resulting in poor contact caused by local overheating and sparking. 3 users improper wire selection, wire diameter and electrical equipment operating current difference is too large, or the quality of the wire failed, together with the alignment and tie in a