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Gamma Three on 2010 steel column
atlas gamma three
post top lantern

This lantern has the advantage of modern appearance as well as meeting the requirements of Lighting Engineers guided by the Code of Practice. Designed to be used with Mercury lamps, suitable for city squares.

Specification

Special Features. One-piece assembly of opal plastic bowl with spigot cap, mounts directly onto column top. On release of toggle catches canopy hinges open to give easy access for installation, maintenance and lamp replacement. When closed the canopy completely seals bowl opening.



Optical System. Symmetrical distribution using 250 or 400 watt mercury lamp providing glare free lighting from diffused globe.



Materials. The canopy is a weather-proofed aluminium spinning and the diffusing bowl from plastic. Stainless steel is used for exterior components to obviate corrosion. The impregnated rot-poof felt gasket forms the seal between the opal bowl and canopy. The spigot cap is cast in aluminium silicon alloy. The seal between the spigot cap and bowl is maintained with a plastic neoprene sealing ring. Great care has been taken to avoid any possibility of electrolytic corrosion.



Finish. The canopy is treated with 'Miracryl' enamel inside and outside to ensure lasting finish and adequate protection from adverse weather conditions.



Installation. The spigot cap has a 3" diameter x 3" long entry and is secured to the column top by three 3/8" BSW socket screws.



Lamps. Atlas 250/400 watt MBF/U fluorescent mercury.



Catalogue Number.
PX.1400 250/400W MBF/U lamps




Polar curve based on average light output from 400 watt MBF/U lamp of 19200 lumens
Technical Data

Atlas Lamps:400 watts MBF/U
Average light output throughout life:19200 lumens
Light output ratio:.66
Light output ratio above horizontal:.09
Light output ratio below horizontal:.57
Light output below horizontal:10950 lumens
Light output per 100 linear feet of footway at:    
    90 ft. spacing12180 lumens
    100 ft. spacing10950 lumens
    120 ft. spacing13120 lumens
Directional intensity ratio:1.6
Total circuit rating:425 watts
Overall diameter:25¼ ins. 63.56 cms.
Overall height:17¾ ins. 44.51 cms.
Weight:15½ lbs. 7.031 kg.
Conversion factor for 250 watt MBF/U:0.57