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Useful Notes:
Guide to Railway
Telephones
©Copyright F. M. Spowart
These notes are uncontrolled and NOT Network Rail endorsed, they are for information and guidance ONLY, NOT for testing or
commissioning purposes.
Guide to Railway Telephones Page One of Six
Telephone Categories:
Railway telephones come into five different categories:
1. CB: Central Battery: These are the most common and are operated by simply lifting the handset*, they are powered remotely via the line wire.
2. MAG: Magneto: These contain batteries to power the circuit, but are still operated the same as the CB type above. Sometimes referred to as ‘LB’ for local battery.
3. AD: Autodial: These have a keypad in which the user enters a number* to call the required location. These are generally connected to a remote telephone exchange.
4. MD: Monodial: These are similar to the CB or MAG, but the user lifts the handset and presses a button which dials a preset number stored in the memory.
5. PETS: Public Emergency Telephone System: These are similar to the above types, but have extra connections which fully monitor features such as handset damaged, off-hook, charger fail, ringer fail etc. *Some phones may require a single button to be pressed.
Types (old and modern): Over the years the telephones have progressed from a few different types to an extensive range, some still used, some obsolete. The main phone manufacturers today are: GAI-tronics Titan Range, DAC Titan Range and Racal ‘RA’ Range. The now least popular ranges are: Plessey 745, Racal RA 705, DAC Commander (mainly used inside control rooms) and the STC selective. Other phones of some type may still be used. The phones are either coloured ‘Goose’ Grey (SPT’s, Point Zone phones etc), or ‘Canary’ Yellow (for level crossing public use). The S.M.A.R.T. option is available on some phones, this stands for self-monitoring and reporting telephone. The Eastern Voice & Data Company seen on the labels on the phones is the company which repairs and refurbishes the phones and returns them to Network Rail via DHL. To give you a perspective on what some of the weather resistant phone cost, the Racal RA 708 (grey) phone Cat No: 87/037883 to purchase costs £586.80, the DAC Titan (yellow) phone Cat No. 87/037918 costs £818.59. All prices include VAT! Source: www.pmctelecom.co.uk
Guide to Railway Telephones Page Two of Six
Standards:
Document NR/L2/TEL/301143 (June 2010) list the relevant standards for lineside telephones specification. Here are just a few important specs listed.
· Ring voltage: 30v to 100v rms. · Line voltage: 20v to 70v DC (20v to 57.5v for PETS system). · 15mA minimum loop resistance (off-hook). · Public intended use phones must have inductive coupling for hearing
impaired people. · All external line cables shall have an external diameter of 7 – 15mm. · The line cable conductor size shall be between 0.5mm – 0.9mm. · Press to call buttons shall initiate a call, but must not disconnect the
handset whilst the button is pressed. · The background noise level in which the speech will not be impaired is
70dB (an equivalent of a large idling lorry with a diesel engine). · All label fonts should be in ‘San Serif’ and a minimum of point 10, black
text on white label. · SPT’s shall be positioned so the user can see all of the elements of the
signal, and permit the user to operate the telephone whilst standing up (approx 1.2 – 1.5m high).
· Unauthorised entry using standard screwdrivers or pliers should not be possible.
· NO additional holes shall be drilled into the mounting plate. · MINIMUM bending radius of the tail cable is; 12 X diameter of cable used. · The following cable colour is used for all phones (although not all may be
used):
Pair A leg B leg
1 Orange White
2 Green Black
Labelling: This should be applied to all phones. Labels which must be attached are; ‘Phonetic Alphabet’, “Lift Handset” or “Press button” instructions, the grid reference of the exact location, the location of which the phone will call, the telephone number of who to contact in an emergency (if applicable), the point number, signal number or LC at which the phone is at. The appropriate SPT or point zone phone stickers shall be attached to the external side of the door. Yellow public phones must have the black phone on yellow background label applied. The “NOT FOR 999 CALLS” sticker MUST NOT be applied to public emergency telephones, these are only used for phones such as; local control phones at level crossings, platform ‘ready to start’ telephones etc. (Check local documents before attaching this sticker). The ‘limited clearance’ sticker shall be applied if applicable to the location. Any other relevant sticker required for that location. (Again check local documents).
The twist in the pairs shall be maintained
Guide to Railway Telephones Page Three of Six
Types of phones in use today:
Cat No 87/037918
Make DAC Titan series
Type AD
Colour Yellow
Use at LC’s
Buttons One (with Number 1)~
Power Remote via line
Cord type Steel type
Cat No 87/037914
Make DAC Titan series
Type CB
Colour Grey
Use at SPT, PZP etc
Buttons None
Power Remote via line
Cord type Steel type
Cat No 87/037888
Make DAC
Type CB
Colour Grey
Use at SPT, PZP etc
Buttons None
Power Remote via line
Cord type Steel type
Cat No 87/037890
Make DAC
Type MAG
Colour Grey
Use at SPT, PZP etc
Buttons Recall button
Power Four type D batteries (Take off front to access them)
Cord type Steel type
~ Number programmed via internal keypad
or via PC program or over another phone
Guide to Railway Telephones Page Four of Six
Cat No 87/037943*
Make DAC Titan series
Type Xing
Colour Yellow
Use at LC’s
Buttons One – push to call
Power Remote via line
Cord type Steel type
Illumination LED illuminated
Cat No 87/037883
Make Racal RA 708 series
Type CB Loop
Colour Grey
Use at SPT, PZP etc
Buttons One – push to call
Power Remote via line
Cord type Steel type
Cat No 87/037885
Make Racal RA 708 series
Type MAG
Colour Grey
Use at SPT, PZP etc
Buttons One – push to call
Power Three type C batteries (Remove black cap at bottom via small allen screws to access them)
Cord type Steel type
Cat No 87/037926
Make DAC Titan series
Type CB
Colour Yellow
Use at LC’s (but NOT for ‘PETS’)
Buttons None
Power Remote via line
Cord type Steel type
*87/037961 will replace this phone in future Designed specifically for PETS I and II
Guide to Railway Telephones Page Five of Six
Other types of phones for reference only:
Accessories: Cable Glands:
Make Gland Type: Brass Gland Type: S/Steel
Titan 54/000099 54/037050
Racal 54/000099 54/037051
Allen Key sizes required to access wiring of phones:
3mm for Titan phones.
5mm for DAC (non-Titan) phones.
6mm for Racal RA 708 phones.
(All phones are pictured above which these tools relate to)
Plessey 745 Racal RA 705
DAC Commander STC Selective (Mechanical) (STC stands for Standard
Telephones & Cables Ltd).
Guide to Railway Telephones Page Six of Six
Specific functions/features present on some (but not all) phones:
Function/Feature Usually set to (if applicable) Used for
Battery Enable switch (Mag type only)
Enabled Connects/disconnects internal
battery
Mute before dialling Enabled Mutes microphone until dialling
has taken place
Call time out link Enabled (user must select a
time)
Set to terminate call after a predetermined limit (if phone
left off the hook)
Loop disconnect NA Impulses used to call a number (most phones now use DTMF)
Time break recall (TBR)
Switchable between three To break the call and try again without hanging up handset
Earth Loop Recall (ELR)
Switch Hook Flash
DTMF (Dual tone multi-frequency) [or ‘LD’]
NA Tones (as opposed to impulses) used to make the call (Touch-
Tone phones)
REN (Ringer Equivalent Number)
NA Number to determine how
many phones will work on one circuit
Basic S&T Faulting procedures:
The S&T department now cover all telephones on the lineside including the actual phone
and tail cable up to the loc or stump box at where it is terminated.
Telecoms cover the main cable into the stump box or loc.
Depending on the fault, the S&T will usually go to the phone first and check for ringing,
hearing and speech. Some faults can be rectified simply by checking the plug points inside
the phone or loose/broken cores.
It is a good idea to use a test phone on the tail cable at the phone and then the loc to see if
the phone is actually faulty.
If the phone seems OK, and the phone is a ‘MAG’ type, check the batteries in the phone, for
all other types the line voltage should be checked at the phone and loc, this should be
between 20 & 70v DC**. A lower voltage will affect the volume of the phone, so this could
be the cause of the fault. If voltage is present at the loc and not at the phone the tail cable is
faulty. If voltage in loc is out of spec or dead, the fault is passed to Telecoms to deal.
Depending on the phone and the fault, the handset part or backplate containing the circuit
parts can be changed instead of the whole phone. Spare unused parts must be returned and
labelled as a ‘working spare’.
A P.E.T.S type system will give a code to the signaller to give the state of the fault and
possible cause.
**This may depend on actual phone used, some phones have a min and max limit.
This document is uncontrolled. It is NOT endorsed by Network Rail, nor is it for commissioning or testing purposes. The relevant
Network Rail documents MUST be used for this. This document is subject to possible omissions and/or errors, therefore the author
cannot be held responsible for any incidents related to railway telephones.
Created & written by F. M. Spowart Network Rail S&T department Retford March 2012 Version 1