. Electric railway journal . the button is depressed is the circuit for the in-dicator closed. The indicator will not clear by the de-pression of the button unless it is also energized by theexternal circuit. In service the indicator is normally de-energized andthe blade stands in the horizontal position. Should atrainman desire to use the switch he pushes the button,and if the indicator clears it shows that there is notrain approaching and that conditions are proper forleaving the siding. As soon as the switch is opened, thesignals leading over the switch and protecting it areset to the stopp
. Electric railway journal . the button is depressed is the circuit for the in-dicator closed. The indicator will not clear by the de-pression of the button unless it is also energized by theexternal circuit. In service the indicator is normally de-energized andthe blade stands in the horizontal position. Should atrainman desire to use the switch he pushes the button,and if the indicator clears it shows that there is notrain approaching and that conditions are proper forleaving the siding. As soon as the switch is opened, thesignals leading over the switch and protecting it areset to the stopposition, therebycausing the indi-cator to assumethe normal, orstop position, andit cannot againbe cleared untilconditions in theblock are re-stored to normal. The time re-lease arrange-ment is employedwhere it is unde-sirable to controlthe switch indi-cator by trackcircuit prelimi-naries, and itprovides a timeinterval equiva-lent to that takenby a train inpassing througha time releasevided with a Switch Indicator with Time ReleaseMechanism is inclosed in an iron box pro-similar to that used on switchThe operation is as follows: A trainman de-siring to use the switch first unlocks the box containingthe time release and starts it by a slight turning of theknob. At the expiration of a predetermined time hedepresses the push button, and if the block is free theindicator will clear. If the indicator clears, the switchmay be thrown and the train can proceed onto the mainline. The first movement of the time release sets allsignals leading over this switch to the stop position, andso long as the time release is in other than the normalposition the signals are held at stop. The throwing ofthe switch continues to hold the signals in the stopposition and restores the indicator to the normal or stopposition. The box cannot be closed and locked unlessthe time release is restored to the normal position so asto close the signal circuits, this action requiring a sm
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyorkmcgrawhillp
