Use
Main road lighting, roundabouts, dock and waterside lighting. This lantern has a cut-off distribution which virtually eliminates glare. The peak candle power is at 70° to the vertical and above this the intensities fall off very rapidly. These characteristics make the lantern particularly suitable for waterside lighting where for navigational purposes it is generally necessary for light to be shielded. Excellent results are also obtained at roundabouts where a cut-off distribution assists visibility. Lanterns should be mounted at 25 ft. and spaced not more than 95-100 ft apart. Suitable for road widths up to 50 ft.

Lamp
For use with a 250W or 400W Osram MA/V lamp.

Mounting
Top entry, standard tapping 1.1/4 in. B.S.P.

Lantern Body
Totally enclosed die-cat aluminium-silicon alloy. The body carries the porcelain terminal block, porcelain cable-cleat, wiring, magnetic deflector, lamp holder, lamp steady, driptray, and the reflectors which make up the optikon.

Lampholder
Porcelain G.E.S. wired with heat-resisting insulated wire to a porcelain terminal block.

Over-Reflector
Immediately above the lamp is a non-magnetic reflector. The reflector plate serves the dual purpose of reflecting light and preventing rising hot air from overheating the magnetic deflector.

Magnetic Deflector
On the reflector plate is mounted a universal magnetic deflector, which is in series with the lamp and consumes 1 watt. The magnetic deflector can be used with either the 250W or 400W lamp, conversion from one wattage to the other being made by changing a connection. The use of a magnetic deflector enables a MA/V lamp, burning horizontally, to be operated with efficiency equally to that of the same lamp burning vertically.

Optical System
Two curved glass mirrors are held inside the body to provide the light control. All mirrors are first quality and are coppered, lead backed and secured by clips. A die-cast light alloy frame, hinged to the body and secured by a stainless steel toggle catch, supports a pressed heat-resisting glass dish.

Weathering Finish
The alloy used is especially selected for its resistance to corrosion and is processed to give a pleasing appearance.

The lantern opened to show optical system, lamp mounting and over-reflector carrying the magnetic deflector

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 lamp characteristics stated; if the latest lamp efficiency is different, the candela or lumen values should be calculated in direct proportion to the relative lamp lumens.

Lantern weight: 26lb (11.8 kg).