Kent Design - Technical Appendix - Kent County Council

design
The test should be carried out using a test instrument
specifically designed for this purpose.
• Operation of Residual Current Devices
This test should be carried out on any such device using
a test instrument specifically designed for this purpose.
A test should be applied at the rated tripping current of
the device and the operating time shall not exceed 40ms
at a residual current of 150 mA.
• Earth Electrode Resistance.
This test is to be carried out in accordance with BS 7430.
• Test Equipment
All test equipment shall be tested and calibrated at
regular planned intervals and no item of equipment shall
be used for testing if test and calibration of the
instrument is overdue.
The instrument to be used for polarity and isolation
testing should always be checked before use against a
known 240 volt supply.
2.8.6.17 AS BUILT DRAWINGS
A set of "as built" drawings shall be provided by the Developer for the
Engineer upon completion of the street lighting installation. All
column positions and private underground cables installed or
realigned for the works must be accurately recorded on these plans.
If manufactured from tubular steel or circular section circumferential
joints shall be of the sleeve type and restricted to points where the
column is designed with reduced diameters. Joints will not be
allowed between designed points of reduced diameter.
2.8.7.2 WALL/ POLE BRACKETS AND CONTROL GEAR BOXES
Wall brackets shall be constructed from steel tube and shall provide
a mounting height of lantern above the carriageway and projections
as specified. “Projection” is the distance measured horizontally from
the wall to the end of the bracket. Brackets shall be provided with a
back plate of adequate size and strength to permit secure attachment
to buildings and to support the lamp and lantern required and shall
be secure by rag bolts or other approved fixings. The brackets shall
be designed to accept mineral insulated cable glands, when required.
Control Gear Boxes shall be constructed of steel or corrosion
resistant alloy and shall be large enough to afford easy access to the
control equipment. Doors are to be fitted with tamper-proof locks of
the same patterns as used for the columns if possible.
A backboard of hardwood or other substantial non-hygroscopic material
shall be fitted into each control box and shall be of sufficient size to
accommodate all of the control equipment, service cable and cut-outs.
Steel wall brackets and control gear boxes shall be hot dipped
galvanised and shall be treated in every respect the same as for the
steel columns, with regard to further protection from corrosion.
The wall brackets and control gear boxes shall be provided with an
earth terminal.
2.8.7 EQUIPMENT SPECIFICATION AND INSTALLATION
2.8.7.1 COLUMNS AND BRACKETS
The lighting column manufacturer shall be registered with and
certified by either BSI Quality Assurance Services, Lloyds Registered
Quality Assurance Ltd, or SGS Yardsley, for the manufacture, supply
and verification of lighting columns under their Quality Assessment
Schedule to BS EN I SO 9000.
Lighting columns and brackets shall be manufactured in compliance
with BS EN 40 Part 1 and BS 5649 parts 2, 3, 5, 6, 7, 8 and 9.
Standard steel columns and bracket arms shall be galvanised and
suitable for the lanterns offered and of a design acceptable to the
Design Council and the Engineer. Columns and brackets shall be
supplied by the same manufacturer.
Columns and bracket arms shall together provide a vertical mounting
height measured from the centre of the light source to the
Carriageway of 5, 6, 8 or 10 metres, or as agreed with the Engineer.
Columns and bracket arms shall have no sharp or jagged edges which
would foul or chafe internal wiring.
The compartment in the base of each column shall be designed to
accommodate control equipment of the lamp or lamps and the
opening(s) in it shall afford easy access to the equipment. The
compartment shall be fitted with weatherproof access door(s) having
tamperproof lock(s) of the same pattern for all columns. A total of six
keys to this lock shall be supplied to the Engineer. Doors shall be fitted
with an earth stud to allow bonding to the main earth terminal. Each
base compartment shall have a base board manufactured from
material which is substantially non-hygroscopic not less than 15mm
thick and of suitable size to accommodate the control equipment with
adequate space at the bottom to accommodate cable terminations
and service cut-outs. The baseboard shall be firmly fixed.
Where agreed with the Engineer columns shall be fitted with a flange
plate. The Developer shall ensure that the spacing of the flange plate
holes and the position of the fixing bolts are compatible.
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Kent
Design
2.8.7.3 EXCAVATION FOR COLUMNS
Excavation for columns shall not be by mechanical means unless
agreed by the Engineer.
The sides of the pits and trenches shall where necessary be
supported adequately at all times and shall be kept free of water.
All excavated materials from such excavations not required for
refilling shall be disposed of in tips provided by the Contractor.
The Developer shall make good with suitable material or concrete
ST2 mix as directed by the Engineer:-
• Any excavation greater than that normally required for
the installation of a column or cable.
• Any additional excavation at or below the bottom of
foundations to remove material which the Developer
allows to become unsuitable.
2.8.7.4 ERECTION OF COLUMNS AND BRACKETS
The Developer shall take any necessary measures to minimise any
disturbance and damage to any trees encountered during erection.
The Developer shall obtain prior approval from the Engineer before
felling, trimming and cutting roots of trees affected by the installation.
Brackets shall be fitted to, and correctly aligned in relation to,
columns before the columns are erected.
The columns shall be carefully aligned and set vertically with doors facing
away from on-coming traffic except where the columns are mounted
behind parapets where the bottom of the door shall be above the
parapet and the door shall be hinged or captive and face towards the
carriageway, or unless otherwise directed by the Engineer. Columns
without flanges shall be erected in a hole with sides as steep as soil
conditions allow and with a clearance of I00mm at the butt end of the
column. The depth shall be in accordance with the manufacturers
instructions unless otherwise agreed with the Engineer. Concrete ST5
mix shall be placed and compacted in 150mm layers to a depth of
600mm above the butt end of the column or to the underside of the
cable entry slot whichever is the greater. The cable entry slots shall be