GE Lucalox Deluxe LU400/DX/40 HPS

While the high efficacy and long life of the HPS lamp makes it eminently suitable for exterior and industrial lighting, its relatively poor colour rendering has excluded it from uses where better colour fidelity is required. The first notable improvement was not achieved until Westinghouse's 1978 introduction of its 250W Ceramalux-4 Deluxe Colour lamp. GE was swift to follow, launching its 250W Lucalox Deluxe in 1980. Whereas competitors quickly added 150W and 400W ratings, GE instead offered an unusually small 70W model in 1987. GE's Deluxe range was not completed until 1990 when 150W and 400W models were finally introduced.

These lamps employ the principle that the spectrum can be further broadened by operation at still higher sodium vapour pressure than in regular HPS lamps. An increase from about 10kPa to 45kPa enlarges the D-line self-reversal width Δλ from around 100Å to 250Å, and substantially more light is produced in the red and blue wings of the sodium spectrum. This boosts the CRI from 20 to 50-70, and CCT from 1900 to 2200K. Since the eye is relatively insensitive to the deep red and blue wavelengths, lamp efficacy is somewhat reduced.

Higher vapour pressure is achieved by shortening the gap behind the electrodes and applying heat reflectors to raise amalgam temperature. Arc tube diameter is also increased, leading to further self-absorption of resonance radiation and still better CRI. Ordinarily such changes would result in a greenish light, which has been avoided by a small increase in the mole fraction of mercury in the amalgam which leads to proportionally more red radiation. Owing to the increased sodium pressure, which reacts more vigorously with the arc tube seals, life is reduced to around 10-15,000 hours.
Manufacturer: General Electric Company U.S.A.
Lamp Power: 400 Watts
Lamp Current: 4.7 Amps 7.0 Amps (starting)
Lamp Voltage: 100 Volts 200-4000V (ignition)
Cap Type: E40s/45 Ni plated brass + vitrite
Bulb Type: ED-89 ED-28 in eighths/inch
Bulb Finish: Clear Lead borosilicate glass
Electrodes: Backwound Tungsten Ba2CaWO6 Emitter
Arc Length: 61 mm 23/8 inches
Atmosphere: Inner: Na,Hg | Xe Outer: Hard Vacuum
Luminous Flux: 37,400 lm (@ 100 hrs) 34,400 lm (average)
Luminous Efficacy: 93.5 lm/W (@ 100 hrs)
Colour Temperature & CRI: CCT: 2200K CRI: Ra 70
Chromaticity Co-ordinates: CCx: 0.505 CCy: 0.415
Rated Lifetime: 15,000 hours to 50% survival
Warm-up & Re-strike Time: 3-4 minutes 1 minute
Burning Position: Universal
Overall Length: 229 mm 9 inches
Light Centre Length: 132 mm 57/32 inches
Factory: Ravenna, OH U.S.A.
Date of Manufacture: August 1998 Date Code: 0898
Original Value: Unknown
References: 1) General Electric USA Brochure, Lampes à Décharge Haute Pression, 6374-482/ILD/F, France, 1980, p.23
2) General Electric International Large Lamp Catalogue, Form 9200, 1987
3) GE Specification Bulletin, Deluxe Lucalox with Mogul Base, Form 206-01037, February 1990
4) The High Pressure Sodium Lamp, Sjef de Groot & Johan van Vliet, Philips Technical Library 1986, pp.301