I've some paper work somewhere that might shed some light on this but I don't unfortunately have it to hand. However from memory each box was assigned a score based on a number of factors including the number of trains dealt with, number and type and quantity of equipment installed etc (hopefully when I locate the paper work I can give a more comprehensive list). The grade each cabin achieved was based on this score and presumably the highest level allowed the cabin to be graded as a TR2 box. The nature of the scoring system was such that I believe the score was greatly enhanced if a cabin controlled one or more remote sites. You will see that all the TR2 boxes listed on the opening post controlled more than one area, and for the same reason one or two other signal boxes which were arguably busier were not included as they only controlled one area (Wembley Park being a prime example,)
I've located the document I was thinking of. However it wasn't quite what I remembered it to be. It in fact details the signal mens' grading structure that was introduced in June 1984 at which time the post of Traffic Regulator (Class 2) was abolished and Traffic Regulator (Class 1) was renamed Senior Signalman.
Nonetheless it makes interesting reading. This new structure appears to be the one that nominally survived up to the Service Control Review of 2005, although doubtless it was subject to modification the time of the Company Plan and as mentioned earlier, effectively ceased to exist after the cabins on the Central Line closed.
Although the document lists each cabin's old Classification (e.g. TR2) it does not explain how this rating was arrived at. It does however go into great detail about how the new rating was calculated.
Under the new scheme each box was given a score and this determined the grade of signalman who worked there.
There were, all together, five grades of signalman (A-E):
Grade | Score | Rate of Pay (1984) |
Signalman A | 1-199 | £98.88 per week |
Signalman B | 200-499 | £108.63 per week |
Signalman C | 500-1249 | £115.79 per week |
Senior Signalman D | 1250-3249 | £7,275 per annum |
Senior Signalman E | 3250 and over | £8,403 per annum |
Relief staff were graded either C or E. The former would cover any A, B or C jobs while the latter would cover any grade. They received an additional ten or fifteen percent allowance according to whether or not they were required to cover more than one location.
The following is the grading for all signalling locations extant in 1984:
Location | Existing Classification | New Rating Score |
Coburg Street | TR1 | 5073 |
Earls Court | TR1 | 4379 |
Finchley Road | TR2 | 1034 |
Aldgate | 14 | 784 |
Wembley Park | 14 | 663 |
Queens Park | 14 | 529 |
Barking | TR2 | 513 |
Whitechapel | 14 | 504 |
White City | TR2 | 424 |
Piccadilly Circus | 14 | 423 |
Rayners Lane | 14 | 408 |
Harrow-On-The-Hill | TR2 | 371 |
Edgware Road (Met.) | 14 | 368 |
Baker Street (Met.) | 14 | 364 |
Willesden Green | 13 | 357 |
Liverpool Street (Cent.) | 14 | 345 |
Woodford | 13 | 332 |
Hainault | 13 | 318 |
Newbury Park | 13 | 318 |
Leytonstone | 13 | 294 |
Farringdon | TR2 | 289 |
Marble Arch | 13 | 286 |
Elephant & Castle | 13 | 276 |
Lambeth North | 13 | 220 |
Rickmansworth | 14 | 220 |
Upminster | 13 | 219 |
Amersham | 13 | 212 |
Stanmore | 11 | 180 |
Hammersmith (Met.) | 11 | 180 |
West Ruislip | 13 | 179 |
Uxbridge | 11 | 179 |
Loughton | 11 | 175 |
Debden | 11 | 144 |
Epping | 11 | 135 |
Canal Junction | 9 | 132 |
Neasden North | 11 | 98 |
Neasden South | 11 | 54 |
So how was the grading score calculated?
Two values had to be calculated, The Traffic Value and The Equipment Value.
Traffic ValueThis was a count of the total number of trains in the timetable using the Monday to Friday service including all scheduled stock transfers, engineers trains and Run as Required train paths. One mark was added for each of the following:
Through Train
Stopping Train
Train routed to siding
Train routed from siding
Starting or terminating train
Reversing train from one line to another (not via a reversing siding)
Train routed to Depot
Train routed ex Depot
Train shunt in depot from siding road to shunt neck.
Where Block Instrument working to BR signal boxes existed an additional mark was available for each of the following:
Each train offered
Each train accepted
Each train passing/stopping
Each train out of section
Where there exists the facility for automatic operation by either King Lever or Automatic Switch operation then the Total Traffic Value thus far calculated will be reduced by one of the following percentages.:
Where up to 5 trains are scheduled to either Reverse, Shunt or Work to and from Depot: 50%
Where between 6 and 30 trains are scheduled to either Reverse, Shunt or Work to and from Depot: 25%
Where equipment allows for automatic reversing: 10%Where there is more than one site in the area under control, the individual Traffic Values for each site are totalled together to provide the final traffic value. This is where cabins with more than one site under their control benefit as each train may well now be counted more than once.
As an aside the document states that the above quoted cabin ratings were produced using traffic values calculated using the 'pre 6th December 1982 timetables.
Equipment ValueFor each item (except automatic signals) in the following list one mark is added to the equipment value. ½ mark is added for each automatic signal.
Equipment:
Main Line Signals and diverging routes
Shunt signals and routes
Calling on signals and routes
Warning signals
Draw up signals
Policeman signals (speed signals without an aspect)
Automatic Signals
Points
Slot Levers on Signals (Neasden North)
Road Traffic Lever (Neasden South)
Yard Controlling Lever
Route Control Lever
King Lever
Auto-Working Switches
Single Line Permission Lever
Switch Box Release Lever
Control Lever For Automatic Washing Facility
Emergency Release Lever
Emergency Release Hand Screw or Switch
Point Release Lever
Block Bell Instruments
Annunciator Displays (Train Destinations) Sections/Panels
Annunciator Manual Cancel Button
Description 'Set Up' Buttons On Describer Panel
Describer Control Machine/Switch/Lever Transmissions
Train Describer (Conventional Type)
Platform 'Next Train' Indicator switches
Floodgate Indications
Rear Cab Clear Indications
Train Ready For Service Indications
Shunter's Acceptance of Train Indicator
Trip-Cock Tester Indications
Low Negative Shoe Indication and Cancel Button
Sidings Traction Control Equipment
Traction Current Indications
Traction Current Acknowledgement Keys
Smoke Alarm Indications
Faulty Train Detector Indications & Cancel Button
Air Gauge Indication
Low Air Gauge Indicator
Flood Warning Indication (Pump Alarms)
Signal Mains Circuit Breakers
Signal Mains On/Off Visuals
Signal Mains Voltage Indication
Delta Track Circuit Release Indications
Whistle Button
Fog Repeater Switch
Signal Floodlighting Switch
Yard Lighting Switch
Track Diagram Switch
Ticket Hall Bell Button
Headway Balanced Control Indications/Switches
Telephones - Number of Terminals in use
Speaker 'Call to Service' Keys
Interval Bells
Train Number Display Visuals
Programme Machine State of Controls Visuals
Programme Machine Second Step Visuals
Programme Machine Warning Visuals
Programme Machine Control Panel
Headway Posts
Engineers Test Train Button
Required to Reverse Sign
Ground Frame Release Button (Manual Override)
Auxiliary Desk Switch
Transfer Ready (Ealing Broadway)
OME Line Possession Button
Staff in Tunnel Button
Train failed in platform Button(Heathrow)
Manual Override Button (West Kensington - Lillie Bridge)
Special Services Buttons
Traffic Notice Sign(s)
London Road Depot Sign
Lock Relay Indications
Automatic Reversing Switch/Button
AC Earth Keys
Single Platform Working Button
Shunt Signal Override Button (Queens Park)
VDU Control Button
Call to Phone Switch
Speaker Circuit to or from
Fog Object
Automatic Train Switch (Woodford/Roding Valley)
Lock and Block Instrument
Conductor Rail Temperature Gauge
Extended Control (Deposits on Rails)
Lock and Block Instrument Line Clear Plunger.
Having added that little lot up then 10% of this figure is added on for each of the following additional responsibilities:
(i) Use of Telephones
(ii) Service Regulation
This produces the total equipment value. This value is then multiplied by the number of hours the cabin is open and divided by the number of man hours employed there. For a cabin which is open twenty four hours a day with only one signalman on duty at any one time the result will be equal to the original total equipment but for a cabin where there are at times two or more signalmen the effect is to reduce the total equipment value as the workload on each individual signalman is deemed to be lower. This calculation produced the final equipment value.
MatrixHaving calculated both the Traffic Value and the Equipment Value a Matrix is referred and the value listed at the point where the relevant traffic and equipment values intersect is the final grading score.