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Beta Four on 1503 steel column
atlas beta four
enclosed lantern

As unobtrusive lantern ideal for many applications its can be used with new columns, wall brackets, conversion schemes or as a replacement unit.

Specification

Special Features. This one-piece body is cast from silicon aluminium alloy. The Perspex or Diakon Bowls are supported by a stainless steel hinge pin and toggle catch. An effective seal between canopy and bowl is provided by a Neoprene gasket. The lantern is suitable for use with Tungsten Filament lamps for 60 to 200W and fluorescent Mercury lamps from 80 to 128W MBF/U.



Optical System. The lantern is available with three separate types of optical system, Diakon refractor bowl, (100 to 150W GLS lamps or 80W MBF/U), Opal Perspex Bowl without refractor (100/150/200W GLS and 80/125W MBF/U) and refractor dome with stippled perspex bowl (100/150/200W GLS and 80/125W MBF/U).

A focussing adjustment to cater for all lamp wattages is incorporated in the lampholder support. The internal reflector plate is anodised aluminium.



Materials. The canopy is cast in LM6M silicon alloy and reflector in anodised aluminium. The opal and stippled bowls are manufactured from plastic sheet and the refractor bowl injection moulded in Diakon.



Finish. The body is finished inside and out in aluminium paint.



Installation. Top entry is provided, tapped ¾" BSP with a grub screw for connection to bracket.

The lantern is marked with "road side" direction for correct orientation.



Lamps. Atlas 100/1500/200W GLS, 80/125W MBF/U.



Catalogue Numbers

Description Complete Fitting
* For 60/150W GLS PEB/Y/2BC.1200
* For 80W MBF/U PEB/Y/3BC.1200
** For 60/150W GLS PEC/S/Z/2BC.1200
** For 150/200W GLS PEC/S/Z/ES.1200
** For 80/125W MBF/U PEC/S/Z/3BC.1200
*** For 60/150W GLS PEB/D/2BC.1200
*** For 150/200W GLS PEB/D/ES.1200
*** For 80/125W MBF/U PEB/D/3BC.1200

For complete catalogue numbers and ordering guide see separate list included in catalogue.

* With asymmetric Diakon refractor bowl.
** With asymmetric glass refractor.
*** With plain opal bowl.




Polar curve based on light output of 2720 from one 80W MBF/U lamp.
Technical Data

ATLAS Lamps:80 watts MBF/U
Average light output throughout life:2720 lumens
Light Output Ratio:0.79
Light Output Ratio above horizontal:0.11
Light Output Ratio below horizontal:0.68
Light Output below horizontal:1844 lumens
Light output per 100 linear feet of footway at:    
    80 ft. spacing2305 lumens
    100 ft. spacing1844 lumens
    120 ft. spacing1536 lumens
Directional Intensity Ratio:2.1
Overall Height:11 3/8ins. 28.9cms.
Overall Diameter:10 1/8ins. 25.7cms.
Weight:6¼lb. 2.8kg.
Conversion factor for 125 watt MBF/U:    1.29
Conversion factor for 100 watt GLS:    0.45
Conversion factor for 150 watt GLS:    0.76
Conversion factor for 200 watt GLS:    1.06