The mutex sign handles mutual exclusion: it blocks trains entering a zone while another train is already inside. Once the zone is freed up again, the waiting trains are allowed to continue movement. This sign is useful in combination with switcher signs to avoid crashing trains. Levers attached to the base block are toggled while a train is inside the mutex zone.
闭塞区间处理：当一列车已经进入闭塞区间，其他列车将不能驶入。闭塞区间清空后，其他列车才能驶入。闭塞区间与转辙器结合使用，可避免列车相撞。当闭塞区间存在列车时，底座连接的拉杆会被切换为开启状态。