HART Railroad — CATS CTC Dispatcher Guide

Publication: DS-CATS-DISP · Rev A · Eff 2026-08-19
Railroad: HART Railroad · Pittsburgh & Chartiers Valley Division · Neville Island Operations
Scope: CATS Digicon panel (HART_Master_CTC_hold.xml), mouse dispatching in CTC mode

Welcome to the desk. This guide is for being a dispatcher on the CATS panel — how you grant authority, line routes, and use fleeting, stacking, and call-on. It is not a software manual (menus, install, Designer, MQTT). For that, see the CATS PDF in tools/cats/release3.2/catsManual.pdf and HART_DIGICON_SYSTEM.md.

Do not duplicate the USS machine guide. HART also has a stock JMRI CTC lever panel (code buttons, N/L/R levers, 15 columns). That machine is documented separately:

→ jmri/layouts/hart/ctc/DISPATCHER_GUIDE.md (DS-DISP)

To run a train automatically between stations (PanelPro, not CATS): ../../jmri/layouts/hart/dispatcher/DISPATCHER_GUIDE.md (DS-AUTO).

Run either CATS CTC or the JMRI USS panel — never both. Both drive Hold on the same masts. CATS ABS is a view-only mimic and is fine alongside either.

At CATS start, LogixNG hides the leftover PanelPro desks: USS CTC (IQC:AUTO:0002, same title on every host), Dispatcher System, and WiThrottle. IQC:AUTO:0004 then hides HART Railroad only — CATS is detected from the running app (cats.apps.Crandic or Windows CatsConfig.xml), not merely from cats.jar on the classpath. PanelPro leaves HART Railroad visible so the geographic desk still works. Reopen USS CTC from the Panels menu when you want the lever machine.

Help and Quit on CTC Panel sit on the bottom button strip (with Restart RPi / Shutdown RPi). The Digicon Dispatcher Panel is schematic-only — no Help/Quit bar. Do not add a second File -> Quit; CATS already has File -> Exit. Quit on the strip uses JMRI Apps.handleQuit() (store prompt, clean shutdown).

1. Reading the Digicon panel

The schematic runs west → east (left → right): Brick → Plane → OS Barn → East End → Princess, with South Yard on the ladder and OS McKees Rocks / OS McKeesport at the east end. It is an interlocking diagram, not a scale map.

On HART, CATS grants routes and throws turnouts; JMRI Signal Logic (SML) computes aspects once a mast is released from Hold. You request permission; the plant decides Clear vs Approach vs Stop from occupancy and points.

At session start, CTC homes are Held (Stop). A successful route Unholds the entrance mast; SML then shows the best aspect the conditions allow.

2. Lining a route (the everyday move)

Quick route — one plant, fixed alignment

Use when points are already lined and you only need the next interlocking step.

1. Confirm the entrance block is unoccupied and no conflicting route is active.
2. Left-click the signal head (not the mast base) at the CP where the train enters.
3. If accepted, the icon colors up and green arrows show the protected path to the next CP in that direction. Turnouts are not moved — the route follows whatever alignment the track already has.
4. To take it back, left-click the same icon again while it is green/yellow, or wait for the train to clear (sectional release frees blocks behind the train).

Tip: Click the lamp head; CATS hot zones are picky.

Extended route (N/X) — multiple plants, CATS lines turnouts

Use when the move needs turnouts thrown across several control points (typical mainline run: Brick → Plane → OS Barn → …).

1. Right-click the entry signal → Set N/X Route → Accept.
2. The entry icon blinks (entry/exit color) — CATS is waiting for the far end.
3. Left-click the exit signal. CATS picks a path (prefers main/normal alignments), waits for turnouts to prove unoccupied, throws points, then builds a chain of quick routes through every CP on the path.
4. To shorten the chain: left-click an intermediate CP (clears that leg) or right-click → Cancel N/X Route (drops that CP and everything beyond).

If creation fails, read the pop-up: no path, blockage, occupied block ahead of the entry signal, or opposing route. Fix points/occupancy or cancel the conflict — do not hammer clicks.

3. When to use what

4. Route stacking

Stacking queues an N/X-style move that cannot run yet (block occupied, opposing traffic, turnout under a train). When the blocking condition clears, CATS runs the deferred route automatically — you do not have to hover over the panel.

Procedure: Same as N/X, but choose Stack Route on the entry signal menu, then left-click the exit. Confirm the stack dialog. Repeat to queue more moves.

Manage the queue: Right-click any signal → View/Change Stacked Routes. The top line is the one waiting for a clear path; delete or reorder from this dialog.

Good HART examples:

• NVL clears Princess; you stack the return move through 113 before the plant is free.
• D749 will need a South Yard setout right after clearing OS Barn — stack it while the train is still east of the plant.
• Opposing meets at East End: stack the second train’s route while the first occupies 111/112.

Cautions:

• Do not stack contradictory paths through the same plant.
• Stacked routes still respect occupancy — they run when clear, not on a timer.
• On large loops, extended-route search can get confused; keep stacks to sensible CP pairs.

5. Fleeting

Fleeting re-creates a route as sectional release drops signals behind a train, so a parade of same-direction trains does not need a fresh click at every plant.

Turn on: Right-click a signal that already has an active route → Turn on Fleeting. On an N/X chain, fleeting applies from that CP through the rest of the chain.

Turn off: Right-click → Cancel Fleeting, or left-click the CP as the train passes (cancels fleeting and can drop the CP from an N/X chain).

HART rule: Fleeting is disabled until a route is ACTIVE — you cannot fleet an idle signal.

When to use: D749 strings, CK1 coke moves, repeated NVL turns in the same direction.

When not to use: Any move where you may need to snatch authority back quickly, opposing meets, or work that crosses the main at a plant you are fleeting through.

6. Call-on

Call-on (Return to Train) is a one-move override: permission to pass a Stop signal into an occupied block ahead — typically to rejoin cut-off cars on the main after a run-around or helper tie-on.

Procedure:

1. Line the turnouts for the join (you keep control; do not grant local switching unless that is your railroad’s rule).
2. Right-click the entrance signal → Call-on → Accept. The icon blinks; the field mast shows Restricting (flashing red / restrictive indication).

CATS will offer call-on only when (all must be true):

• The immediate block in front of the signal is not occupied.
• The next block is occupied (the cars or train you are joining).
• No track authority or out-of-service on those blocks.

End call-on: Cancel from the signal menu, or when the immediate block becomes occupied (the engine entered the overlap).

Alternatives: Grant track authority on the fouling turnouts and let the crew switch themselves; or line a quick route out to the main and flag the return (no CATS feature — verbal permission).

7. Other dispatcher tools (brief)

8. Rules of thumb (HART)

1. One dispatcher, one CTC authority — CATS CTC or JMRI USS, not both.
2. Signals govern — if the mast is Stop, the train stops. If CATS rejects a route, find occupancy, points, or an opposing reservation before overriding.
3. Line switches before you expect diverging clears — quick routes do not throw turnouts; N/X does.
4. Do not move points under a train — CATS waits on turnout safety delay; still check the schematic.
5. Use stacking for choreography, fleeting for parades, call-on for joins — not interchangeably.
6. West Yard ladder (116 / 103) and South Yard Switch 17 are yard territory — no CTC homes. Westbound into OS Barn from the yard lead is the T6 dwarf on the 117 plant. K-stub tracks are restricted speed beyond the dwarfs, prepared to stop.
7. Refresh Screen is safe after glitches; avoid Refresh Layout during ops (pushes panel state at JMRI).

9. Quick reference

Office of the Superintendent · Neville Island Operations · DS-CATS-DISP Rev A