From the Kiosk No. 3 onwards, all the kiosk range had internal lighting.  Originally this was achieved with a 25 watt bayonet bulb fitted in a brass, batten style, light fitting.  This lamp fitting had a special ring which would only release the bulb with the use of a special tool, the "Spanner, Long, Lampholder".

Controlling the lamp was a time switch.  These could vary in nature from a simple on/off type to the GPO Venner time switch.  The correct position for these was under the board board and to the left.  The electrical intake would generally be to the right.  In some areas the time switch has been located in other positions, one of them being at the top of the back board!

By the 1960's most of the time switches were installed in a Cases, Time Switch, No. 2 (Drawing - P/EL 538), which would have a Time-switch No. 2 and Solar Dial No. 2 fitted within.  The time switch was interesting as it had a solar dial that could be easily changed.  The GPO used 9 different Solar Dials depending on the location of the kiosk.  The Solar Dial switched the light off half an hour before sunrise and on hour an hour after sunset taking into account the month of the year.  The Solar Dials were labelled A to K and their locations are show below.

The box containing the Venner time switch was lockable with a special key and on the right hand side, on early boxes, there was a non-lockable toggle switch for testing the light.  This switch can be seen to the top right of the picture below.

There were two variants of Solar Dial, the No. 1 and No. 2.  Solar Dial No. 1 fitted a Time-switch No. 1 and the Solar Dial No. 2 fitted the Time-switch No. 2.

The GPO negotiated an electrical contract price for electricity and this was based on the hours of use.  There was no meter and just a fuse box on the electrical intake cable.

In the early 1970's fluorescent fittings were installed in all Kiosks and the time switches removed.  The fuse box was then covered with a semicircular plastic cover, coloured red.  This cover and the light cover are fixed in place by triangular headed bolts.  See the article below for more details.

At a date unknown, BT changed the electrical installations in public kiosks to a none earthed type.  Only double insulated fittings were used after installation.

None of the P/EL diagrams appear to be available.

Electrical installation - Power, General C3500
Lighting of Telephone call offices - Power, Lighting A3101
Operating times of solar dials - Power, General C3502
Power supply agreements for call offices - Power, General A0502
Provision of lighting in kiosk and cabinets - Telephone, Call Offices A3007


Cases, Time Switch No. 1 with Solar Dial No. 1.
This time switch is fitted with the D type of the solar dial.
The solar dial is the round calibrated object.
The solar dial is calibrated to adjust the time dependant on the month of the year.

Picture taken in 1938 showing the Venner time switch and incoming fuse unit.

Key No. 2 for Case, Time-Switch (Drawing - P/EL 443)


Cases, Time Switch, No. 2 with cover open.
Fitted with Solar Dial No. 1 (C type).
The lamp test switch is the lower right of the picture.

Close up of the Solar Dial No. 1 (C type)

Cases, Time Switch, No.2

Cases, Time Switch, No.2 with cover open


Solar Dial location map


11 Lighting
Issue 1, Sept 1971


All new kiosks should be equipped with fluorescent lighting and all existing kiosks converted from tungsten to fluorescent lighting as quickly as possible. The new lighting installation is of the double insulated earth free type and the kiosks are artificially illuminated throughout the 24 hour period.

The limited number of kiosks at present connected to time switch controlled street lighting supplies should be considered for conversion to normal supplies, the deciding factor being the comparison of costs between additional maintenance outside normal working hours of the fluorescent lighting installation and capital expenditure on re-connection of supply.

2.1 Kiosks No. 2

2.1.1 Fittings EL Fluorescent No. 12A 200/220 volt or 230/250 volt.
2.1.2 Telephone Kiosk Pattress Assembly (modified in accordance with Drawing P/EL 897).
2.1.3 Guard Kiosk No. 6 Intake Power Equipment.
2.1.4 Keys for Fittings EL (to release diffuser, operate switch in pattress and secure Guard fixing screws).
2.1.5 Fittings EL Fluorescent No. 12B 200/220 volt or 230/250 volt, to be fitted only when vandalism is excessive.

2.2 Kiosk No. 6
2.2.1 Fittings EL Fluorescent No. 12A 200/220 volt or 230/250 volt.
2.2.2 Telephone Kiosk Pattress Assembly.
2.2.3 Guard Kiosk No. 6 Intake Power Equipment.
2.2.4 Keys for Fittings EL.
2.2.5 Fittings EL Fluorescent No. 12B 200/220 volt or 230/250 volt, to be fitted only when vandalism is excessive.

2.3 Kiosk No. 8
2.3.1 Fittings EL Fluorescent No. 12B 200/220 volt or 230/250 volt.
2.3.2 Telephone Kiosk Pattress Assembly (modified in accordance with Drawing P/EL 878).
2.3.3 Guard Kiosk No. 8 Intake Power Equipment.
2.3.4 Keys for Fittings EL.

Luminaires (Fittings EL Fluorescent Nos. 12A and 12B)
The luminaires are double insulated bulk head type complete with diffuser and lamp(s).  The 12A has a single 8 watt 12 inch lamp and the 12B twin 8 watt 12 inch lamps.

Telephone Kiosk Pattress Assembly
The pattress is manufactured in plastic shaped to fit the kiosk roof dome, presents a flat base for the luminaire and incorporates a double pole insulating switch. The pattress assembly includes fuse-box, plastic conduit, cable, conduit clips and fixing screws.

Guard Kiosk No. 6 or 8, Intake Power Equipment
The Guard is manufactured in plastic and provides a mechanical protection for the electricity supply cut-out and Post Office fuse-box.

4.1 General
When converting existing kiosks from tungsten lighting the Electricity Board should be requested to disconnect the supply, remove the steel guard that may be protecting the cut-out and disconnect any earth connection that may be obtained from the incoming supply cable sheath. If the cut-out is too large to be accommodated beneath the new Guard Kiosk No. 6 or 8, a request should be made to the Electricity Board to fit a smaller cut-out.

For new kiosks a connection to the main supply should be negotiated with the Electricity Board. A connection to a time switch controlled street lighting scheme should be avoided.

4.2 Kiosk Nos. 2 and 6
Install equipment as indicated on Drawing P/EL877.

4.3 Kiosk No. 8
Install equipment as indicated on Drawing P/EL878.

5.1 Insulation Resistance
The installation shall be tested initially and subsequently at 5 year intervals and on every occasion that any part of the equipment - excluding the lamp and starter switch - has been replaced, the insulation resistance should not be less than 10 megohms.

5.2 Sequence of testing

5.2.1 Initial Installation Operate pattress switch to on and check continuity at cable ends of cut-out tails with suitable tester. Test for insulation resistance between the cut-out tails and (i) the kiosk metal, (ii) the metal case of the luminaire and (iii) the luminaire gear tray, and also between the metal case and the gear tray.

5.2.2 Subsequent testing
The tests should be in accordance with 5.2.1 except that the neutral be tested for zero voltage with a voltage tester and then disconnected at the PO fuse box, the PO fuse removed and the test applied at the outgoing circuit terminations.

Lamp replacement
Lamps should be changed at periods of not more than 10 months on a planned area basis.

Component exchange
If any part of the installation requires replacement, with the exception of fuses, lamps, starter switches or diffusers it is advisable that the entire component, pattress assembly or luminaire, be exchanged completely.

Details in connection with limits of authority for the provision of kiosk supplies are given in TI D5 H0017.

Standard agreements have been arranged with all Electricity Boards for the supply of energy to kiosks fitted with either tungsten or fluorescent lighting at fixed annual charges.

The provision of lighting in cabinets is covered by TI E3010.

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Last revised: February 28, 2023