电动火车司机桌上的一种指示器，指示电流从架空电线或电缆中被抽出A system of railway electrification in which the traction current is picked up by a skate or shoe which makes contact with a third rail located between or to one side of the running rails, and returned via both or either of the two running rails.
" class="glossaryLink ">第三轨. 当线路灯丢失（且无法重置）时，表示可能存在故障。这需要立即注意以避免严重损坏。
