Pittsburgh & Lake Erie Railroad
Historical Society

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Pittsburgh & Lake Erie Railroad,
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Two Color Signal Aspects


The information on this page was compiled from
the instruction manual printed by the Pittsburgh and Lake Erie Railroad,
LEARNING THE NAMES OF SIGNAL INDICATIONS,
dated July 1, 1979.
 

 

The name of the signal displaying two RED lights is STOP SIGNAL.

The name of the signal is read from the top position down. When Red is used with Green or Yellow, Red is not considered because it contributes nothing to the name of the signal. It remains lighted to let you know it is in working order and to show the relationship of the other light - whether in top or bottom position.

Putting it another way - "If it's not all Red, it's not Red at all."


 

The addition of a number plate displayed with a STOP SIGNAL indication changes the name to STOP AND PROCEED. The train must STOP AND then may PROCEED at Restricted Speed.

Restricted Speed definition - Proceed prepared to stop short of train, obstruction or switch not properly lined; looking out for broken rail and not exceeding 15 miles per hour.

Signals with NUMBER PLATES are not controlled by the Train Dispatcher of Operator. They automatically respond to track occupancy. Signals without NUMBER PLATES are called HOME SIGNALS and, but for a few exceptions, are all controlled by the Train Dispatcher or Operator. The few exceptions are covered in Timetable Special Instructions. A controlled HOME SIGNAL will normally display STOP except when lined for an immediate movement.


 

The name of the signal with a Green light over a Red light is CLEAR. This means the train may proceed at Normal Speed which is the maximum authorized speed.


 

When the Green is in the bottom position, the name is SLOW CLEAR - SLOW because the Green is in the bottom position and CLEAR because the color is Green. SLOW CLEAR means to proceed at Slow Speed.

Slow Speed Definition - Not exceeding 15 miles per hour.


 

Flashing a signal increases the speed instruction conveyed. This is considered a fail-safe system because if the flashing unit fails the steady light will indicate a lower and safer speed. When the Green is flashing in the bottom position the name is LIMITED CLEAR - LIMITED because the Green is in the bottom position AND flashing and CLEAR because the color is Green. LIMITED CLEAR means to proceed at Limited Speed.

Limited Speed Definition - Not exceeding 45 miles per hour


 

When the Yellow color is in the top position it means APPROACH. APPROACH means to approach the next signal prepared to stop and a train exceeding Medium Speed must at once reduce to that speed.


 

When the Yellow drops to the bottom position, it loses its identity as Approach and becomes the most restriced speed. The name is RESTRICTING.

RESTRICTING means to proceed prepared to stop short of train, obstruction or switch not properly lined; looking out for broken rail and not exceeding 15 miles per hour.

A steady Yellow on the bottom is ALWAYS Restricting.


 

When the Yellow is flashing in the bottom position the name is LIMITED APPROACH - LIMITED because the Yellow is in the bottom position AND flashing and APPROACH because the color is Yellow. LIMITED APPROACH means to proceed at Limited Speed preparing to stop at the next signal.

Limited Speed Definition - Not exceeding 45 miles per hour


 

When a signal has a Yellow in the top position and a Green in the middle position, it's name is APPROACH MEDIUM.

APPROACH because the color is Yellow and in the top position.

MEDIUM because the second color, Green, is in the bottom position.

APPROACH MEDIUM means to proceed approaching the next signal at Medium Speed..


 

When a signal has a Yellow in the top position and a Green in the middle position and flashing, it's name is APPROACH LIMITED.

APPROACH because the color is Yellow and in the top position.

LIMITED because the second color, Green, is in the bottom position and flashing thus upgrading the speed from Medium to Limited.

APPROACH LIMITED means to proceed approaching the next signal at Limited Speed.