Powerball HCI-T Ceramic Metal Halide

The Powerball concept of Osram Ceramic Metal Halide lamps is based on the same technology as the low-wattage "BULGY" arc tubes employed in the same company's American products under the Sylvania brand name. The technology was first announced in 2001 for the USA market, and then in higher wattages for Europe in mid-2002.

The fundamental difference is that the arc tube has been redesigned from a cylindrical shape to a new ellipsoidal form. Ellipsoidal arc tubes made in a single piece of ceramic have been known before, but are extremely expensive due to the advanced production methods that are required. The Powerball arc tube is made in two parts with a seam around the centre, and is the result of a co-operative project between Osram, Sylvania and NGK Insulators of Japan. It has the advantage that it is much cheaper to manufacture than the single piece ceramic arc tube.

An ellipsoidal shape is advantageous because it ensures that the arc tube temperature is more uniform than in the usual cyldindrical design. Crucially the ends run hotter, and this means that less metal halide salt dose is required. Corrosion of the ceramic by the halides is then substantially reduced and this allows overall arc tube temperature to be raised slightly, with this having a consequent benefit in terms of raising lamp efficacy and colour rendering. Thus Osram's Powerball design is able to raise luminous efficacy to 104 lm/W and colour rendering is increased from Ra85 to Ra89.

The new arc tube also has much lower thermal mass than earlier designs. This results in a faster run-up time and also a much shorter delay before hot-restriking the discharge.
Manufacturer: Osram GmbH
Lamp Power: 248 Watts
Lamp Current: 2.9 Amps
Lamp Voltage: 105 Volts
Cap: E40s/45
Bulb Finish: Clear
Bulb Type: T-46
Overall Length: 226 mm
Light Centre Length: 150 mm
Electrodes: Backwound tungsten
Atmosphere: Inner : Argon Outer : Hard Vacuum
Luminous Flux: 25,800 lm
Luminous Efficacy: 104 lm/W
Colour Temperature & CRI: CCT : 3000K CRI : Ra 89
Chromaticity Co-ordinates: Not published
Rated Life: Not published
Factory: Spandau, Germany
Date of Manufacture: May 2002
Original / Present Value: