Z.9425 Side view of lantern. Sectional scale drawing. The iso-candle is based on an average lamp light output through life from a 140 watt OSRAM Sodium lamp. (7,980 lumens) . 85 w. 140 w. Directional intensity ratio 1.9 2.0 Light above horizontal 7% 7% Light output ratio 70% 70%

LANTERN for LARGE SODIUM LAMPS The interior of the lantern as seen from below.

Main road Lantern for Sodium Lamps.

Use Main road lighting; mounting height 25 ft.; spacing 120-150 ft.; raod width 30-40 ft. For roads over 40 ft. in width, this lantern, with its horizontally burning lamp, will give better results than are obtainable from a lantern with a vertical burning light source.

Lamp Z.9425. For use with 85 w. or 140 w. OSRAM lamp.

Mounting Top entry. The lantern is tapped 1¼in. gas and is supplied with a lock-nut.

Lantern Body Die-cast light alloy. The body consists of three castings with are two end pieces and a sloped top. Two longitudinal mild steel rods of rust-proof finish hold the lantern rigidly together. A lamp steady slides on these rods and can be adjusted to suit the length of lamp in use. An earthing screw is provided.

Lampholder Porcelain B.C. The lampholder position is fixed. It is wired with heat-resisting wire to a terminal block mounted on the end of the lantern.

Optical System
The optical system consists of two Z.6313 G.E.C. prismatic refractor plates. They are supported by small detachable lugs on end castings, this arrangement allowing the refractor plate to be quickly removed if required. Each plate has its refracting prisms sealed by a palin cover glass, thus ensuring that all exposed glass surfaces are smooth. A small saving in cost can be effected by the omission of the cover glasses but this will usually necessitate more frequently cleaning of the refractor plates. Immediately above the lamp is a white enamelled inner over-reflector. This can be easily removed when the lantern is to be wired.

Weathering Finish The light alloy used is specially selected for its resistance to corrosion. Further protection is obtained by the use of a suitable primer, undercoat and matt aluminium finish top coat.

Erection Instructions Erection is so simple that no instructions are necessary. No focusing is possible.

Alternative Body Z.9435 lantern is also available made in cast iron. Its construction and optical performance are the same as the Z.9425. It weigths about 40 lbs. (18.1 kgs).

Back to: GEC Street Lighting