Self-ballasted Mercury Vapor Lamp
date: label: date made
content: ca 1978
name: label: maker
content: Jewell Products Inc.
notes: label: Description (Brief)
content: This lamp was designed as a retrofit for mogul based, 1500 W incandescent fixtures. Discharge lamps such as mercury vapor lamps require a ballast to prevent self-destruction. The goal with this product was to improve energy efficiency in the luminaire without requiring installation of a separate ballast. Also, the light emitted by the incandescent filament in this lamp would provide a minimal amount of color correction for the blue-green mercury discharge. Characteristics: brass mogul-screw base with glass insulator. Side-tipped, quartz arc-tube with two main electrodes (tungsten coil-on-coil on mandrels), twin tungsten starter electrodes (adjacent to the main electrodes), multi-piece leads (stranded wire to solid wire to flat plate to ribbon to molybdenum wafer to electrode), flat presses. Mercury condensed on and around upper electrode. A C-7A tungsten filament (with 5 two-piece supports mounted to a glass bead affixed to one support frame-member) acts as a ballast resistance and is in series with the arc-tube. Crimp connectors on leads, spot-welds on mount-structure. Resistors are in series with each starting electrode. Lead to upper starting electrode parallels the main support-spine and is held in place via a glass-bead insulator. Mica heat shield just above stem-press. Getter dispenser mounted near stem-press. Tipless, PS-style envelope. See Duro-Test form 992 (High Intensity Discharge Lamps), page 3; and form 971-8210GTO15M (Fluomeric Lamps). Cardboard collar (to retain lamp in package) found with lamp. Given to donor by an engineer who rescued the lamp from a south Baltimore warehouse which was being demolished around 1981. Fluomeric is a registered trade-mark of Duro-Test (as per 1955). Richard Neubert of Duro-Test reported that Jewell was a subsidiary of Duro-Test until 1981, and marketed the lamp under the trade name "Super Lumen" until around 1975. The trade-names were then consolidated and Jewell sold Fluomeric until 1981.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
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content: Energy & Power
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content: Electric Lamps
creditLine: label: Credit Line
content: from Harold D. Wallace, Jr.
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 2003.0030.04
label: accession number
content: 2003.0030
label: catalog number
content: 2003.0030.04
objectType: label: Object Name
content: discharge lamp
physicalDescription: label: Measurements
content: overall: 15 1/4 in x 7 in; 38.735 cm x 17.78 cm