Cab Signals

The cab signals that are used on LIRR MU's and locomotives, can they be used on Amtrak, Metro-North, or former Conrail lines in PA? What happens when LIRR runs over the Hell Gate?
If it does work, then can a P&W or CSX engine be run on the LIRR?

Thanks
Jason

They can be used, but are not corresponding to the speeds for ATC on MNCR or Amtrak. anytime LIRR equipment is used it needs to be run with Form M to give proper speeds and to instruct engineer about different rules on their equipment.

Actually, the LIRR cabs are compatible with the standard american 4 aspect cab signal system and do use the same or lower speeds.

These are the code rates and signals/speeds shared by LIRR/Amtrak/Et al

Pulse Rate == Speed == Signal

0 == 20 == Restricting

75 == 30 == Approach

120 == 45 == Approach Medium

180 == 80 == Clear

The LIRR uses two additional aspects...

270 == 55
430(?) == 65

So Amtrak/MNRR equipment might not run properly on the LIRR.

Incidently, The LIRR equipment MUST work properly on the Amtrak/MNRR system because the stretch of track between HAROLD and A runs on NORAC signals with the Amtrak/MNRR cab signaling.

Metro North might be a bit anal about things, but it's best not to ever use them as a standard for comparason.

the speeds are not same as Diesel equipment however and since the LIRR electric equipment is incompatible anyway.

Jersey Mike,

Just to complete the picture (this is for LIRR EMU equipment only):

180 cpm = 80 mph
270 cpm = 70 mph
420 cpm = 60 mph
120 cpm = 40 mph
75 cpm = 30 mph
50 cpm = 15 mph
no code = 15 mph

All speed aspects are nominal. The actual enforced speeds are slightly different.

Be advised that there is no adjustment for wheel wear in M-1s. There is adjustment for wheel wear in M-3s and M-7s.

Note also that no code rate is a direct multiple of any other. Likely to prevent harmonic overtones from having any possible effect.

Metro north only has 4 aspects. and on freight engines the mode switch switches from pass/freight, all other equipment is pass only.

180 cpm (normal cab)is max authorised track speed (only restriction is equipment restriction)max speed freight is 45 mph

120 cpm(limited cab) is 45 mph passenger and 30 mph freight.

75 cpm(medium cab is 30 passenger 15 mph freight.

0 cpm(restricted cab) or no code is 15 passenger/freight
(on Amtrak/CSX/P&W equipment the Restriced is set for 20 mph).

N340SG wrote: 50 cpm = 15 mph

Hmmm, I've never heard that one ever discussed here before and it dosen't seem to make much sense that they would have both a 50 code and a 0 code leading to the same cab signal. Can you provide some more information on the use of this mysterious 50 code? Is it a new thing? Does it make a differance in terms of train operation? I checked US&S and they do sell 50 bpm generators so your story is not altogether implausable, but I also went through the Railroad Signaling yahoo group and there had been no mention of it there either:

Railway Signaling wrote:As for the codes used: for PRR/PC/CR (conventional 100 Hz code): 0 code =
Restricting, 75 = Approach, 120 = App Medium, 180 = Clear. Only LIRR (of
the US railroads) uses the 270 and 420 codes.

Anyway, the LIRR system should be fully compatible on the Amtrak system which is the same as the MNRR system. The Form M thing that DRN was talking about is probably due to the use of a 15mph Medium Speed for freight trains. Since the NY&A would be the only ones you'd see venturing onto MNRR on any regular basis this problem would arise. Still, this is a reult of MNRR's pig headedness in terms of freight. Anywhere else it wouldn't be a problem.[/quote]

What are the cab speeds for LIRR Diesel equipment?

NY&A does not operate on MNCR and can not lead on MNCR.
I have run several Diesel excursions for LI Sunrise chapter and always needed a trainorder due to different spees on MP15's and powerpacks.

Jersey Mike,

I don't believe the 50 code is actually used anywhere on the LIRR, but it is there nonetheless. Take it from an ATC qualified Electrician who has been testing and repairing these things for 19 years.
The LIRR infrastructure supports a six code, seven aspect system as outlined in my post.
Any code can be set for whatever MPH restriction is desired.
The descending order to more restrictive code does have to be 180-270-420-120-75-50-no code, however, because the audible warning device is interlocked accordingly. (I.E., There should be no audible warning when a less restrictive code is received.) The associated relays on M-1 and M-3 are C (180), B (270), A (420), R (120), L (75), D (50), or "Could Be A Really Long Day".

Just to confuse things a little: If you look at the ADU in an OEM M-1 or M-3, you will see all seven aspects can be displayed. The ADU displays a zero aspect when there is no code. EMU cars outfitted with the Microcab package, (overhauled M-1, all M-3 [eventually], and all M-7) will display a 15 aspect when no code is present. If you look at M-7 cab pictures, there is no zero aspect at all!

Tom

P.S. LIRR Engineers will confirm that when they do the departure test in the M-1 and M-3, both the true 15 code and no code (zero mph aspect) are tested.

P.P.S. Or take a look at this: http://members.aol.com/N340SG/362.jpg

Thank you for the information. For the sake of needing to be definite on this issue I will continue to not count the 50 code as an LIRR cab signal until it is entered into service. So give me a ring if they do.

Just to confuse things a little: If you look at the ADU in an OEM M-1 or M-3, you will see all seven aspects can be displayed. The ADU displays a zero aspect when there is no code. EMU cars outfitted with the Microcab package, (overhauled M-1, all M-3 [eventually], and all M-7) will display a 15 aspect when no code is present. If you look at M-7 cab pictures, there is no zero aspect at all!

Tom

P.S. LIRR Engineers will confirm that when they do the departure test in the M-1 and M-3, both the true 15 code and no code (zero mph aspect) are tested.

It had always been reported here that the 0 on the M-1/3's was the overspeed indicator and not the no-code indicator.

Actually, it does both.

In an overspeed condition in the OEM M-1 and M-3, the more restrictive aspect and the zero aspect will illuminate until the overspeed is cleared.
If there is a more restrictive aspect received, but the train is not in an overspeed, both the more restrictive and zero aspects will illuminate until the acknowledge button is pressed.
In a no code condition in the OEM US&S M-1 and M-3, the zero aspect illuminates. Not the 15 aspect.
US&S Microcab equipped M-1 , M-3, and M-7 cars show a 15 aspect with a no code condition.

howardr142,

An Engineer would have to help you out with LIRR diesel ATC aspects.
I know MAS (Maximum Authorized Speed) was 65mph with the old equipment. I don't know if they upped that any with the DE/DMs.
I haven't touched a diesel ATC system since I was an apprentice 19 years ago.

Tom

So, there's (50) for 15mph, and no code's 15mph too, was the LIRR ever thinking of making one or the other a true 0, i.e. enforce a full stop (presumeably the 50 code - a brake dump with every no code situation would suck)??

Has the LIRR ever thought of PTS, too?

Oh yeah, while I'm at it - A few years ago between NHP and Mineola, these mysterious yellow square thingies appeared between the rails on both tracks, spaced every few hundred feet. Does <b>anyone</b> know what the heck those were for? AFAIK, they went away after a few months.

On the OEM M-1, it looks like they did want a no code condition to do something different. The no code circuit was supposed to energize the ZSR (Zero Speed Relay). Instead, the ZSR is not used, and the circuit from a no code was rewired to energize the 15SR (15 Speed Relay). That's why the overspeed trip points are always exactly the same for 50 code and no code. The same circuit is used for both. A similar design was apparently carried over to the M-3.

My guess is that a lower speed was never implemented because there are so many places where there is no code present.
If you wanted to, let's say, lower the no code speed to 5 or 10 mph for yards and whatnot, then you would have to encode a 50 code into Jamaica and it's interlockings, Penn Station and it's approaches, and all the other places where there is no code, but 15 mph is desired.
Sound plausible?
(BTW: A train limited to 5 or 10 mph may have a tough time getting up the hill into WSY in certain situations.)

Tom

P.S. I've not heard any talk about LIRR Positive Train Control Systems.