Turnout Reference

Turnout Reference
Maximum speed for diverging moves	15 MPH	30 MPH	45 MPH	80 MPH
Turnout/crossover designation	#10	#15	#20	#32.75
Distance between switch points for 13' 0" track centers	195' 3"	289'	381' 11"	600'
Home signal aspect	Restricting	Medium Clear	Limited Clear
Distant signal aspect	Approach Slow	Approach Medium	Approach Limited

The semaphore arm signals are representations of position light signals used by the Pennsylvania Railroad.

The signals shown are based on the NORAC rule book, which uses speed signalling. Diverging routes will have the signals shown above, and straight routes will have the Clear signal shown.

The turnout designation is roughly based on the ratio of the width of the frog (the piece of metal where the two rails cross) to the length of the frog. A larger number means a sharper angle, and therefore a faster speed is allowed through it. Because the railroads typically used standard layouts for their turnouts and crossovers, there could be standard speeds for all turnouts, based on the frog number or designation. This allowed for signals to have specific speeds attached to them.