The pre-signal only considers actual exit signals when deciding whether to go green or remain red, even if there are other, non-exit signals that would allow a train to leave the block.

• 预处理信号在决定是否开放绿灯，或维持红灯时只会顾及出口信号当下的状况，就算有其它非出口信号允许一辆列车离开区块亦然。