Specification Clearside 8254/5
Side road lighting; the lantern is designed for mounting at heights between 15 ft and
18 ft and at a spacing of 100-120 ft.
The lantern is very suitable for use on housing estates, especially in new towns.
Two 2 ft. 40W Osram fluorescent tubes
The Z8254 side entry lantern requires not less than 5 in. of horizontal unthreaded 1.1/4 in.
B.S.P. When fully home two 7/16 in. Allen-type grub screws grip the barrel. The design allows
for the lantern to be elevated slightly if this is required to add to the appearance of an
The Z8255 top entry lantern requires 2 in. of threaded 1.1/4 in. B.S.P.
One-piece silicon aluminium alloy die-casting. The gear and wiring necessary to operate the tubes
is fitted to a removable tray screwed to bosses in the body casting. The body also carries the
two lampholder supports.
An earthing screw, porcelain terminal block and porcelain cable cleat are provided.
Light control is obtained by two 'Perspex' refractor plates. The prismatic sides of the plates
are bonded, one to each inner side of a 'Perspex' bowl. Both inner and outer surfaces of
the bowl are smooth for easy cleaning. A white over-reflector is a secondary component of the optical
system. The inside of the body and the ends of the enclosing bowl are given a matt finish
to diffuse stray light and give the lantern a pleasing appearance. The enclosing bowl is held to
the lantern body by stainless steel toggle clips and toggle hinges. A tropicalised felt gasket
between the body casting and bowl ensures a weatherproof seal when the lantern is closed.
The alloy used is specially selected for its resistance to corrosion. Further protection is
obtained by the use of pre-treatment primer and silver top coat, stoved on.
|The Z8254 lantern. The bowl has been lowered to show the tubes.
The polar curve is based on an average tube life from two 2 ft. 40W Osram white fluorescent
tubes (2880 lumens average).
|Directional intensity ratio||2.0:1|
|Light above horizontal||25%|
|Light output ratio||80%|
|Lumens in the lower hemisphere ||1730 |
Light distribution data are given for the guidance of the lighting engineer and represent the
average results of laboratory tests on a number of lanterns taken at random from stock.
The data are based on the tube characteristics stated; if the latest tube efficiency is different,
the candela or lumen values should be calculated in direct proportion to the relative tube
Lantern weights: Z8254 Complete with gear: 25lb (11.3 kg)
Lantern weights: Z8255 Complete with gear: 23lb (10.4 kg)