SimSig Call Types
Every call RailComms can receive from SimSig, the reply options
available, and what each reply triggers. Calls marked with
Readback require the driver to
repeat the authority back before the action is confirmed.
Driver Signaller Shunter Technician Public Auto
A train is held at a signal displaying a red (danger) aspect. The driver is requesting instructions.
Example "Driver of 4Q08 waiting at red signal VC833"
Reply options Wait 2 minutes #0
→ Driver waits 2 min then calls back if still red.
Wait 5 minutes #1
→ Driver waits 5 min then calls back if still red.
Wait 15 minutes #2
→ Driver waits 15 min then calls back if still red.
Pass signal at stop Readback #3
→ Driver passes the red signal under authority. Requires headcode + signal confirmation.
Examine the line Readback #4
→ Driver proceeds cautiously to check for obstructions.
Pass at stop & examine line Readback #5
→ Driver passes signal and examines line ahead.
The signal lamp has failed and is showing no aspect. Same urgency as a red signal but different wording.
Example "Driver of 2W89 waiting at unlit signal T151"
Reply options Wait 2 minutes #0
→ Driver waits 2 min then calls back.
Wait 5 minutes #1
→ Driver waits 5 min then calls back.
Wait 15 minutes #2
→ Driver waits 15 min then calls back.
Pass unlit signal Readback #3
→ Driver passes the unlit signal under authority.
Pass unlit signal & examine Readback #4
→ Driver passes signal and examines line ahead.
A signal changed to a more restrictive aspect after the driver had already seen and reacted to a less restrictive one.
Example "Driver of 2W50 reporting an adverse change of aspect at signal 32"
Reply options Continue after speaking to control #0
→ Acknowledged. Driver continues.
A train is delayed at a location. SimSig reports the reason and estimated departure time.
Example "1C51 delayed at Three Bridges due to a technical fault, expected to depart at about 14:15"
Reply options No, signal not replaced #2
→ Signal stays red; driver waits for expected departure.
Yes, signal replaced #1
→ Signal cleared; driver can depart when ready.
The driver is questioning the route set at a signal because it does not match their booked route.
Example "Driver of 5M04 is querying the route set at signal VC662: booked via Balham"
Reply options Wait 5 minutes #0
→ Signal may be replaced; driver waits and calls back.
Abandon timetable #1
→ Timetable abandoned; train follows whatever route is set.
A train that was previously delayed or held has resolved its issue and is ready to resume.
Example "2B10 is ready to depart from Clapham Junction"
Reply options Ok #0
→ Acknowledged. Driver departs when signal clears.
Follow-up call after a driver was instructed to examine the line. Reports whether the line is clear.
Example "No obstructions found on the line ahead"
Reply options Continue normally #0
→ No obstruction. Driver resumes normal running.
Continue examining line #1
→ Driver continues cautious examination.
A train or shunter is at a CSD entry point requesting permission to enter the yard/siding.
Example "5A20 is ready at entry point Farnham CSD (WK440), scheduled 07:16"
Reply options Permission granted #0
→ Train enters the siding/depot.
Call back in 5 minutes #1
→ Entry denied for now; shunter calls back later.
Another signaller advising that a train is running ahead of schedule and will arrive in your area early.
Example "I have 4022 running early via Aynho Junction. It can be in your area at about 05:00"
Reply options Let the train continue #0
→ Train continues running early through your area.
Hold until booked time #1
→ Train held at boundary until its booked time.
A neighbouring signaller reporting they have a train waiting in their area, usually at your boundary.
Example "I have 1L33 waiting at Honiton"
Reply options Wait 5 minutes #1
→ Hold the train 5 min.
Wait 15 minutes #2
→ Hold the train 15 min.
Crew is in position but the train hasn't arrived yet. Auto-dismissed by RailComms (unrealistic call type).
Example "Crew for 7V81 is ready and waiting for the train to arrive at East Croydon"
Reply options Ok (auto-dismissed) #0
→ RailComms auto-answers and dismisses silently.
A technician reporting that a previously reported infrastructure failure has been repaired.
Example "Signal failure in the Interlocking ST (Selhurst) area fixed"
Reply options Ok #0
→ Acknowledged. Failure record cleared.
A member of the public at a user-worked crossing requesting permission to cross the line.
Example "Hello, this is Margaret at Barton Mill crossing — I'd like to cross please"
Reply options Ok #0
→ Permission granted to cross.
