GE American Fluorescent PowerGroove F96PG17-CW

The development of high power fluorescent tubes has resulted in several designs peculiar to the American market. The first such lamp was the 5-foot T17 of 1939. Then in 1954 GE developed 'HO' High Output lamps - starting with the 8-foot 100W which marked the first use of the recessed-double-contact R17d base for electrical safety.

Further increased output proved difficult to achieve, owing to the physics of the low pressure mercury discharge which becomes increasingly inefficient at higher loadings due to increased electron density. Mercury ions begin to come into Local Thermal Equilibrium with the electron temperature, and their rate of quenching almost equals the rate of excitation. The output of standard lamps cannot be increased by more than 2.5 times even at any power input.

The problem was solved by John Aicher and Eugene Lemmers of GE, who had invented a high ouput non-circular fluorescent lamp in 1943. The further improved shape of the PowerGroove lamp featured here allowed an increase to 2.2 times the normal light output with only 2.5 times the power dissipation. The indented glass tube decreases the distance mercury ions diffuse to the wall, thereby increasing the ambipolar ion loss rate, which in turn increases electron temperatures. This leads to reduced electron density, and hence increased lamp efficacy. The first lamps had long single-sided grooves, and lamp power and output were increased further in 1960 with this double-grooved lamp, which fits the arc of a 9-foot lamp into an 8-foot tube. Mercury vapour pressure is kept low (to maximise efficacy) by two special slanted grooves which produce a cool spot near the tube centre, and two missing grooves at one end.
´╗┐Manufacturer: General Electric U.S.A.
Lamp Power: 215 Watts
Lamp Current: 1.50 Amps
Lamp Voltage: 163 Volts
Cap Type: R17d Aluminium
Bulb Type: TD-54 TD-17 in eighths/inch
Bulb Finish: Cool White 3Ca3(PO4)2.Ca(F,Cl)2:Sb,Mn
Electrodes: Triple-Coil + Anode Plates Triple Carbonate emitter
Discharge Length:
Atmosphere: Hg | Ar
Luminous Flux: 14,000 lm (@ 100h)
Luminous Efficacy: 65.1 lm/W (@ 100h)
Colour Temperature & CRI: CCT: 4100K CRI: Ra60
Chromaticity Co-ordinates: CCx: CCy:
Rated Lifetime: 10000 hours
Warm-up & Re-strike Time: 1 minute Instant
Burning Position: Universal
Nominal Length: 2438 mm 96 inches
Factory: Circleville OH U.S.A.
Date of Manufacture: August 1987
Original Value:
 
References: 1) "Allis in Wonderland - Physics for Profit and Fun", by J.F. Waymouth, Physics Today, Vol.54 No.2, June 2000, pp.38-42
2) GE #9200 Lamp Catalog, USA, 1987
3) US Patent 2,482,421, Flat Tube Electrical Device, A.E.Lemmers, Filed 21-Oct-1943
4) US Patent 2,916,645, Tubular Lamp Envelopes (PowerGroove single-sided), A.E.Lemmers, B.Shaw, J.Salo, Filed 17-Apr-1956
5) US Patent 2,915,664, Tubular Electric Lamp (PowerGroove improved shape), A.E.Lemmers, Filed 09-Apr-1956
6) US Patent 2,973,447, Grooved Lamp Vapor Pressure Control (PowerGroove asymmetric grooves), J.O.Aicher & A.E.Lemmers, Filed 12-May-1958
7) US Patent 2,950,410, Multiple Groove Discharge Lamp (PowerGroove improved efficacy), J.O.Aicher & A.E.Lemmers, Filed 23-Sep-1960