介绍鉴定安全滑触线合格的四大标准：
Qualified appraisal safety sliding contact line four criteria:
1、滑触线膨胀问题，长度超过100米以后就要考虑膨胀问题。
1, the sliding contact problem of linear expansion, will consider expanding problem length more than 100 meters.
2、电压降问题，根据各种铜条长度电压降也有所不同。
2, the problem of voltage drop, according to all kinds of copper bar length voltage drop is also different.
3、碳刷的使用寿命，安全滑触线属于易耗品，行驶的距离不利于设备的维护。
3, the service life of carbon brush, safety sliding contact line belong to the consumable, driving distance is not conducive to maintenance of the equipment.
4、集电器性能，主要从轮子使用寿命、转弯轮设计和集电器是否满足各种环境下使用。
4, collector performance, mainly from the service life of the wheel, turning round design and collector whether meet all kinds of environments.
