Pro anchor time not too long to shorten the interval between each sub-step, to avoid the trolley wire wear and at the middle of each span wires thrash wear.
The anchoring time should not be too long, as far as possible to shorten the interval between the sub-processes, to avoid wire wear at the carriage and wire in the middle of the gear to whip each other wear.
The temporary anchoring time shall not be too long, and the interval time between sub processes shall be shortened as far as possible to avoid the abrasion of conductor at the pulley and the abrasion of conductor in the middle of span.