Railroad Terms

Glossary of Terms

Road Channel - the "dispatch" channel. ALL trains will ONLY monitor the road channel except passenger trains which may monitor an additional channel in case of emergency or tactical reasons.
Yard Channel - channel used for yard operations and coordination
Hump Channel - channel used in a yard for hump operations. (Where cars are moved with gravity and switches from a hill or hump to the train.)
PBX Channel - Private Branch Exchange mobile phones for Admin units and grounds people wishing to contact other people throughout the division.
Carmen - workers in yards coordinating individual cars on the tracks.
EOTM - End of train monitor, a steady stream of brakeline and air pressure data.
AAR - Association of American Railroads - series of channels from 07 to 97 between 160.215 and 161.565
ABS - Automatic Block Signaling - a computerized signal system unmanned. These occur in the yards and very busy stations.
CTC - Centralized Traffic Control - The dispatcher is in Omaha, Nebraska in a centeralized dispatch center covering the whole western US.
DTC - Direct Traffic Control - the dispatcher for this section is in a tower or able to physically be at the block to direct the traffic. Not many of these are around anymore.
H (Trackside Detector) - Is a Hotbox Detector
D (Trackside Detector) - Is a Dragging Equipment Detector
HW (Trackside Detector) - Is a High and Wide Detector
Block Signal with "P" Plates - The black "P" is located on a triangle with a silver background. This sign is mounted on a signal. "P" means protected and that the signal it is attached to is protecting something ahead. That signal is activated by a special protective device ahead. When the signal is RED besides following all standard procedures for a RED signal, an inspection from the ground must be made to the protected structure, train, or track before the train can continue past the RED signal. The train does not have to stop if the engineer can inspect the protected area from the cab of the engine and declare it safe for passage. Any RED signal must be reported to the dispatcher.
Setout - Take a car anywhere on the train that needs to be released or causing problems and place it alone on a siding or spur.
Pickup Opposite of setout - picking up an engine or car from a siding or spur line.

Terms/Letters found on my railroad lists
ABS - Automated Block Signal (computerized signalling)
BRT - Block Register Territory
CTC - Centralized Traffic Control (dispatcher controlled)
DT - Double Track
DTC - Direct Traffic Control (local tower/dispatcher controlled)
GO - General Order
MofW - Maintenance of Way - the track maintenance
OMT - Other than Main Track
OOS - Out of Service
RL - Restricted Limits
TWC - Track Warrant Control
#MT - Multiple Main Tracks, # represents number of tracks
YL - Yard Limits
A - Automatic Interlocking
D - Drawbridge
E - End of Track or Branch
F - Flagged Passenger Stop
G - Railroad Crossing protected by Gate
J - Junction with another track
L - Balloon Track or Loop
M - Manual Interlocking
P - Scheduled Passenger Stop (Amtrak, etc)
R - Restricted Limits
S - Railroad Crossing protected by Stop Signs
T - Turning Facility or Wye
U - Railroad crossing not protected
X - Crossover
Y - Yard Limits

Slang words and others
"Searchlight" Signals or "Target" Signals - These are the lonely one-bulbed signals around most sidings and high incidence areas that need signaling. They have one lens capable of producing 3 colors by a rotating roundel. These are neat to watch change as a train passes from Green to Red. You can see the roundel inside rotating past Yellow/Orange to Red from Green. (A good place to witness this is Hooker Creek Road in Tehama County right at the railroad crossing.)

Tricolors - These are replacing the searchlights by a traingle shaped signal (still round face) but three seperate lenses and bulbs for the three colors. You can see these along the UP track between Los Molinos and Vina in Tehama County or along the track near Rawson siding between Proberta and Red Bluff (Hwy 99w).

WigWags - a very ancient crossing arm that isn't even an arm. This is an overhead warning system placed at crossings that by magnetic relays and such, wig-wag a hanging disc back and forth down over the cars. In the middle of the arm is a red light. So the cars basically see a waving red light over the tracks telling them to stop. A great example of this is on the Santa Cruz Big Trees and Railroad line. A small tourist excursion line - in Santa Cruz these wigwags are in operation and protect the mainline that travels down the middle of the road from sidestreet traffic that could pop out. These are funny looking but have a lot of history with them. I believe Sacramento Railroad Museum has one on display in front and the Shasta Cascade Railroad Preservation Society *might* get a wigwag for display but I have no details.