It is suitable for use with Horizontal burning Mercury lamps either 250W or 400W and can be supplied with or without Magnetic Arc Control, which is wired in series with the lamp.

The body casting and ring are of corrosion resisting aluminium-alloy, the bowl ring being hinged to the body at one end, with a robust quick-release catch at the other end. The bowl assembly is sealed with a gasket fixed to the flange of the body casting which cushions the heat-resisting glass bowl and ensures a dust-proof enclosure.

The heat-resisting glass bowl is designed with a rippled exterior pattern which diffuses the light rays and gives a good daylight appearance.

The lamp holder bracket is screwed to the body casting and is reversable when an alternative size lamp is required.

The magnetic arc deflector, when used, is also fitted to the underside of the hood casting, so that all the wiring is contained in the hood, the control leads being connected to the terminal block without further complications.

The optical system consists of a specically designed reflector combination to control and redirect the light from the lamp given above the horizontal.

The curved upper reflector controls the upper zone, which the lower secondary reflectors, in the form of louvers, control the lower zone. The combination gives a wide lateral distribution with a maximum efficiency of directed light up and down the thoroughfare.

The reflectors are made of Super Purity aluminium sheet polished and anodised.

Polar Distribution Curves Of M-400 With 400W Mercury Lamp
Based On The Initial Lamp Output Of 16800 Lumens



Iso-Candle Of M-400 With 400W Mercury Lamp