Track-closing
signals are simple signs, which inform about
inability of entering the particular track. In some
cases standard 'dead-end' sign is replaced by the
light-signal reflecting permamently S1 signal
('stop'). When Z1-group signal is reflected, it means
passing it it strictly prohibited. Dead-end signs
always colaborate with other signals (for example Z2o
[entering the turntable allowed] signal is followed
by M2 ]'shunting allowed']).