A.安全門未關(guān)閉,能發(fā)出調(diào)平、換層和開(kāi)車信號(hào) B.安全門關(guān)閉后才能發(fā)出開(kāi)車信號(hào) C.罐籠未到位,放不下?lián)u臺(tái),打不開(kāi)阻車器 D.搖臺(tái)未抬起,阻車器未關(guān)閉,發(fā)不出開(kāi)車信號(hào)
A.1 B.2 C.3 D.4
A.1h B.2h C.3h D.4h