I have selected Tomar Industries as the provider of signals based on the old B&O.
I am confused with Lunar White that is sometimes part of the signal. You could find it to the top of the post, below the signal on the post or even both top and bottom.
Why is Lunar White there? What is the best way to use these signals on the railroad and where would they go?
Lunar usually means “restricting”. Proceed prepared to stop short of something. What position depends on the signal.
For example Rule 289 Permissive: lunar over red over red, Block occupied, proceeed prepared to stop short of train ahead, in automatic block territory, proceed at restricted speed until entire train passes next signal.
Or Rule 290 Restricting: red over red over lunar, block occupied, proceed prepared to stop short of train ahead, in automatic block territory, proceed at restricted speed until entire train passes next signal.
Dave H.
Now the light comes on. Thank you!
The rules for the B&O that I have been able to study indicate that for all Signal Colors Lunar is restriction as well if it is on.
For example, Lunar over Green just before a crossover track switch tells the engineer to slow through the crossover and regain track speed speed once the caboose is clear. Do I have that right?
Does the restriction of Lunar show the engineer, regardless of his situation that he must have the train under control ready to stop short?
The 1953 B&O rule book doesn’t show a lunar over green indication.
Dave H.
Hmm.
http://www.railroadsignals.us/
B&O CPL’s
http://www.railroadsignals.us/cplindex.htm
This is what I am working off of at the moment. Hopefully that helps understanding of where I am at on this topic.
Absolutes and TO Signals are crystal clear and not misunderstood.
Im still fuzzy on Permissives and Blocks. Im thinking of the ABC block system protecting one train as it travels.
First my confusion. You weren’t asking about “lunar” signals, you were asking about the white lights surrounding the CPL’s. Lunar isn’t white.
As far as i can tell a white light directly over a CPL means, well, nothing. for example white over green is “Clear” meaning proceed. White over yellow is “approach”. White over red is “stop”.
A white light above and to the left of a green is “Approach medium”.
A white light below a green is “Medium clear”.
A white light below a yellow is “Medium approach”.
A white light below a lunar is “Medium permissive”
A white light below a red is “Stop and proceed”.
A white light below and to the left of a green is “Medium approach medium”.
So it looks like they use the white lights as qualifiers for the regular CPL signals.
Truly a unique system.
Dave H.
Rather then using a second signal head, the B&O used one CPL head, plus the white pilot lights above and below the CPL head. To protect against burned out pilots, the indication displayed by the CPL alone is the most restrictive version of it.
Clear - pilot centered over green.
Limited Clear - flashing pilot centered under green.
Medium Clear - pilot centered under green.
Slow Clear - green w/ no pilot.
Approach Limited - flashing pilot, above left of green.
Approach Medium - pilot above left of green.
Approach Slow - pilot above right of green.
Approach - pilot centered over yellow.
Medium Approach - pilot centered under yellow.
Slow Approach - yellow w/ no pilot.
Restricting - lunar w/ no pilot.
Stop and Proceed (or Restricted Proceed depending on era) - pilot centered over red.
Stop - red w/ no pilot.
Nick
check out this link from Al Krugs page… but please note that the only place where any lunar white would be used on an B&O CPL is in the restricted indication… all the other lights shown as white are infact white…
http://www.alkrug.vcn.com/rrfacts/signals/ColorPosition/sigrules_BO.htm
csx engineer
Ok I have the Lunar settled. If this is shown then it is restricting no matter what.
The steady white light must mean absolute, if a CPL is Green up and down and shows a white at the top, it’s absolutely track speed clear. If shown at the bottom white it’s restricting.
Makes me wonder how they want that train to be driven? The Engineer? Or the Dispatcher? Not just position in a block but speed and switches are involved here.
Restricted speed yes, “restricting” no. Lunar at a left 45degr angle is “permissive”.
No, an abscence of a number plate on the signal mast or a “A” sign on the signal mast means “absolute”.
A white pilot light over horizontal red is “stop and proceed”, which is NOT an absolute signal.
There is no such indication as “absolutely clear”.
Not according the the 1953 B&O rulebook. A white pilot light above a vertical green signal is “Clear”. A white pilot light below a vertical green signal is “Medium clear” which doesn’t involve restricting at all.
What’s the confusion? The dispatcher sets the route and clears a signal, the position of the signals and the occupancy of the track drives the signal system to tell the engineer what speed to go. Very simple Once you learn what the signals mean.
Dave H.
The signal indications have a speed or speeds associated with them and a location where the speeds apply.
There are 4 speeds in the B&O signal system:
Track speed : whatever the speed is normally on the track (determined by the physical characteristics of the track).
Medium Speed: Not exceeding 30 mph
Slow Speed: Not exceeding 15 mph.
Restricted Speed: Prepared to stop short of train, obstruction,switch not properly lined or broken rail
There are two general location descriptions, the speed approaching the next signal and the speed the train should pass the signal or next signal and/or switches.
The indications are a combination of a speed or speeds and a location or locations the speeds apply. They don’t tell the engineer where he’s going, they just tell him how fast he should travel and where.
So the signal system tells the engineer what speed to proceed at or when to stop. The dispatcher doesn’t pick which signal to display. FRom the dispatcher’s perspective, the switches have only two positions, normal and reverse, and the signals have only two states, cleared or not cleared. In CTC or at an interlocking, once he lines a signal the signal system itself, the relays in the cabinet, determine what exact indication the train recieves, based on the positions of the switches and which route has been lined/signals have been requested. In Automatic Block Signal territory, the indications are totally driven by the positions of the switches and the occupancy of the track, the dispatcher has no say in what signal is displayed.
An Absolute signal is defined in the B&O rules as: A fixed interlocking or automatic block signal without a number board, the most restrictive indication of which is “Stop”. Contrary to your assumption, the lack of a marker light or a lit marker light makes the signal absolute, not that there is one on top.
By the way the B&O rules refer to themain colored pair of lights as a “cluster” an
Thank you. Posts such as this makes the Forum very valuable in learning new things.
I dont know if anyone can stand one more question. But here goes.
If a CPL holds a bracket equippted with two marker lights above, what do I expect from this type of signal?
Which lights are lit and what color are they?
Depending on where the lights are, whether they are lit or not and what color the cluster is, the B&O 1953 shows 10 possible different indications that could be displayed.
Dave H.