Discussion of the past and present operations of the Long Island Rail Road.

Moderator: Liquidcamphor

  by nyandw
MP54D CAB Location #5 Cab signal lamps appliance - 3 aspects were 15, 30, MAS initially had position light aspects-clear, approach and restricting
Note the “15” the “30 and MAS” are faded or not visible in this photo

Further historical insights as to the evolution as it pertains to the M1-M3?
  by C-LINER 2001
The first Locomotives equip with Seven aspects in service was the 1968 Alco C-420's 222-229.
Last edited by C-LINER 2001 on Tue Mar 14, 2023 7:22 am, edited 1 time in total.
  by C-LINER 2001
Steve, No Sir.
  by workextra
With the 3 code system the ASC covered MAS and limited speed with the “MAS” aspect? Or did you get a “30”/“Approach” aspect for limited speed?
Because on the 3 aspect system there is no 45 or limited speed aspect.

With an aspect of approach medium.
Say west of kew Gardens on ML4 approaching Jay with a Medium Clear.
With the 3 aspect system, did you get the “30” at the approach medium or somewhere between it and the medium clear at Jay, or did you get the “30”
Aspect “AT” jays home signal on the metropolitan signal bridge?

It appears there was some mixing and matching with the installation of the CSS on LIRR.
The use of the 3 aspect system created issues when the limited speeds switches were installed. This lead to medium
Speed being 30 or 40 in ASC (cab signal) territory. Then the 45/40 aspects came on line with the upgraded system.

However, the rules weren’t updated nor was the code or signals to display the proper aspects.
Today this plagues the operation.
With only 4 codes use MAS (80) (70) (30or40) (15)
The “60” is only used for the switches that are greater than limited speed but less than MAS. (60 mph switches). As the definitions of the speeds do not provide for any speed between MAS & Limited speeds)
Keeping this solely based on the 100hz PRR system predominantly used on 90% of LIRR CSS territory.
  by Engineer Spike
I never asked my uncle before he passed away about the compatibility of the Long Island and PRR cab signals. Dos LIRR equipment need to conform or are they required to use the PRR system on the lines into Penn Station?
  by west point
do they use Amtrak ACSES?
  by nyandw
C-Liner wrote: The first Locomotives equip with Seven aspects in service was the 1968 Alco C-420's 222-229.

Any photos of where these were located within the cab?
  by workextra
The LIRR used a watered down version of the PRR system.
The “cab signals” are technically not aspects but speeds to so in conjunction to the code pulse rate.
The LIRR MAS code is set for 80
Limited speed 40
Medium speed 30
Restrict/Slow speeds 15
The ADUs do not display actual signal aspects, however there is talk to adopt the standard ADU Amtrak uses going forward.
There are also additional speeds associated with different pulse frequencies.
70 (kind of used as a “reduced” MAS)
60 ( primarily used for 60mph switches as there is no defined lower speed between limited and MAS to protect the speed through these switches for which you get a clear signal) also used as a second reduced MAS for the Long Beach branch)

Then you when your grand central
Speeds of 65/55/45/20 which used a 200hz system
And is not compatible with the PRRs
System 100hz
So those speeds are:
MAS 60
Limited 55
Medium 45
R/Sl- 20
However there is no code in GCM so you still Pick up the default 15 restricted speed.
This system is 100% incompatible with LIRR as it’s the reduced aspect type signal Aspects in the field Associated with this system.
but keeping with the LIRR (PRR) system they don’t need more than 5 fixed speeds associated with the traditional aspects, than when displayed with the Amtrak Style ADU would conform
With the LIRRs 3 color reduced aspect signals.