NATIONAL BUREAU OF STANDARDS REPORT

3U8U

%

REPORT

on

THE LUMINOUS FLUX OF FOUR LAMPS

for

THE NATIONAL PHTSICAL LABORATORY

Ray P* Teele

<NBS>

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
u. S. DEPARTMENT OF COMMERCE

Sinclair Weeks, Secretary

NATIONAL BUREAU OF STANDARDS

A. V. Aslin, Director

THE NATIONAL BUREAU OF STANDARDS

The scope of activities of the National Bureau of Standards is suggested in the following listing

of the divisions and sections engaged in technical work. In general, each section is engaged in

specialized research, development, and engineering in the field indicated by its title. A brief

description of the activities, and of the resultant reports and publications, appears on the inside

of the back cover of this report.

Electricity and Electronics. Resistance and Reactance. Electron Tubes. Electrical Instru- ments. Magnetic Measurements. Process Technology. Engineering Electronics. Electronic

Instrumentation. Electrochemistry.

Optics and Metrology. Photometry and Colorimetry. Optical Instruments. Photographic

Technology. Length. Engineering Metrology.

Heat and Power. Temperature Measurements. Thermodynamics. Cryogenic Physics.

Engines and Lubrication. Engine Fuels.

Atomic and Radiation Physics. Spectroscopy. Radiometry. Mass Spectrometry. Solid

State Physics. Electron Physics. Atomic Physics. Nuclear Physics. Radioactivity. X-rays. Betatron. Nucleonic Instrumentation. Radiological Equipment. AEC Radiation Instruments. Chemistry. Organic Coatings. Surface Chemistry. Organic Chemistry. Analytical Chemistry.

Inorganic Chemistry. Electrodeposition. Gas Chemistry. Physical Chemistry. Thermochemistry. Spectrochemistry. Pure Substances.

Mechanics. Sound. Mechanical Instruments. Fluid Mechanics. Engineering Mechanics.

Mass and Scale. Capacity, Density, and Fluid Meters. Combustion Controls.

Organic and Fibrous Materials. Rubber. Textiles. Paper. Leather. Testing and Specifications. Polymer Structure. Organic Plastics. Dental Research.

Metallurgy. Thermal Metallurgy. Chemical Metallurgy. Mechanical Metallurgy. Corrosion.

Mineral Products. Porcelain and Pottery. Glass. Refractories. Enameled Metals. Concreting Materials. Constitution and Microstructure.

Building Technology. Structural Engineering. Fire Protection. Heating and Air Conditioning. Floor, Roof, and Wall Coverings. Codes and Specifications.

Applied Mathematics. Numerical Analysis. Computation. Statistical Engineering. Mathematical Physics.

Data Processing Systems. Components and Techniques. Digital Circuitry. Digital Systems.

Analogue Systems.

Cryogenic Engineering. Cryogenic Equipment. Cryogenic Processes. Properties of Materials.

Gas Liquefaction.

Radio Propagation Physics. Upper Atmosphere Research. Ionospheric Research. Regular

Propagation Services.

Radio Propagation Engineering. Frequency Utilization Research. Tropospheric Propagation

Research.

Radio Standards. High Frequency Standards. Microwave Standards. • Office of Basic Instrumentation • Office of Weights and Measures
NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT NBS REPORT

0201-20*0205 October 1955 3U8U

Report

on

THE LUMINOUS FLUX OF FOUR LAMPS

for

The National Physical Laboratory

by

Ray P* Teele

Photometry and Colorimetry Section

Optics and Metrology Division

(File Ref* 1100)

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

in part, is prohibited

andards, Washington

port has been specifisport for its own use,

The publication, re|

unless permission Is

25, D, C, Such peri

cal ly prepared If tl

Approved for public release by the

Director of the National Institute of

Standards and Technology (NIST) on October 9, 2015

Tin© Luminous Flux of Four tamps

foy

The National Physical laboratory

by

Ray P. feel©

This report describes the method of measurement and gives the values

of luminous flux for four lamp standards of the National Physical Laboratory.

These four NPL standards are designated as group 199 39 in this report.

These standards have been measured a number of times both at the National

Physical Laboratory and at the National Bureau of Standards as well as one time at the Bureau International des Poids et Mesures, '

1* Purpose

The measurements were made to assist in establishing the relationship

between the unit of luminous flux for gas-filled, tungsten-filament lamps

as realized at the National Physical Laboratory and at the National Bureau

of Standards*

2. Material

The lamps are of a special type used by the National Physical Laboratory

and have a 300-watt, 200-volt nominal rating. They have been returned to the

NFL by a staff member of the NBS who carried them by hand to avoid the

danger of damage by commercial shipment.

3* Previous Measurements

The lamps were first measured by the NPL in 195>0 $ measured by the NBS

twice, returned to the NPL and remeasured by the NPL in 1952? and measured

by the BIPM and again remeasured by die NPL in 195>3* In the present r eport

the earlier results are summarized and the results of the 195>5 measurements at the NBS are given.

The results of the 19f>0 to 19J>3 measurements are given in the first

six rows of Table I* The last row gives the average result for the present

measurements*

Table I* Average Values for the Four NPL Lamps (Group 199 39)

Operated at the Currents Given in Table II

cr I Date Voltage Lumens

NPL 1950 192,

2

fi 1*228

NBS 1952 (Feb.) 192. 2[j 1*188

NBS 1952 (May) 192.

3

0

1*182

NPL 1952 192. 1*8

1*231

BIPM 1953 192 « 2o 1*260 (1992 unit)

NPL 1953 192.32 1*233

NBS 1955 192.3a 1*216

-2*

1* • Present Measurements

The four lamps of group 199 39 were measured at tile same time as the

four standards recently taken to the BIPM for the forthcoming (1955-56)

international intercomparisons by using MBS reference groi$> §8?2A as standards. The unit represented by the NBS values for the 1955*56 international inter comparisen lamps and by the KBS 1955 values for the NPL

lamps is, consequently, tiie same.

The paIred-determinations method of Youden and Conner* was used to

in ter compare four NBS reference groups of standards. Group 587 2A is one of these four groups and was shown by this intereomparison to be representative of the four groups of reference standards to within 0.1 percent.

Thus the 1955 values reported herein may be considered to be based upon

all four of the NBS reference groups of gas-filled tungsten-filament lanps

rather than upon a single group of standards.

The values for the individual lamps are given in Table II.

Table II. Values for NPL Lamps, Group 199 39

Lamp Amperes Volts Lumens

(Set)

199 A 39 1.5701* 19U.00 U356

199 D 39 1.51*20 189.76 1*012

199 J 39 1.5588 192.30 1*231

199 0 39 1.5608 193.22 1*265

Average 192.32 1*216

5* Discussion

The NBS unit of luminous flux at 2788**K has been represented in

•the international corapariscns of 191*8 and 1950-52 by a group of four

lamps, NBS 2288, NBS 2289, NBS 2290, and NBS 2291, hereinafter designated as the IBS 2288 group. The records cn these lamps show the

results giiasn in Table III*

New Experimental Designs for Paired Observations. W. J. louden and

\S. S. Conner, IBS J. Research, Vol. 53, No. 3, September 195U,

R. P. 2#32f
I
-3-

Table III. Average Values for Four NBS Lamps (Group NBS 2288)

Date Laboratory Lumens

Keported Corrected to

1952 BIPM Ttoit

September 19U8 NBS (Report II8363) 2327

December 19U8 BIPM (Letter 12-2-U9) #2377 2371a

February 19h9 NPL " " 2338

October 191a9 BIPM " *2375 2372

June 1950 BIPM **2365 2372

February 1951 NBS (Report 127556) 2377

December 1951 BIPM **2361 2368

October 1955 NBS 233U

£L9ii8 provisional BIPM unit

#*191a8 definitive BIPM unit

It does not seemjr in view of the 19H8 and 1955 NBS values that the

high value obtained at the NBS in 1951 represents the NBS unit. The

average of the original 19U8 value and that now found is 2330 lumens.

Comparing this with the NPL 191a9 value of 2338 lumens, we get a ratio of

1.003. We would expect the same ratio for measurements on the NPL 199 39

group of lamps at the two laboratories. Our 1955 measurements, reported

in Table II, result in an average of 1*216 lumens and the NPL average is

U230, giving a ratio of 1.003. The ratio of the NPL average of 1*230 to

the NBS average of 1*195 is 1.008.

We can find no explanation for the high values found for the NBS

2288 group of lamps at the NBS in 1951* particularly since the NPL measurements on this group of lamps made in 19h9 seem concordant with the NBS

19U8 and 1955 values.

One additional indirect check on the NBS unit is furnished by an interlaboratory check test carried out in this country in 1951a. A group

of 100-watt gas-filled tungsten-filament lamps was measured at the NBS

and 6 commercial laboratories. The average of all of the seven participating laboratories was 1606 lumens and the NBS value was 1606 lumens.

This is pointed out to indicate that the unit of luminous flux at 2?88C'K in general use in this country is in good agreement with the unit represented by Ihe values both herein reported for the NPL lamps and reported

to the BIPM for the lamps in the 1955“56 international intercomparison

now in progress.

The ratios of the units of the NBS and NPL to the 1952 BIPM unit

can be determined from -the data on the two groups of lamps (NPL 199 39

group and NBS 2288 group) given in Tables I and III. These ratios are given in Table IV.
. ' ' a9

.. " - .
Table IV. Ratio of Ihits at 2788°K to BIPM 1952 Unit

(Average of U values in Column 1* of Table III = 2371.

Date Laboratory

19U8 NBS

19U8-1951 BIPM

19U9 NPL

1951 NBS

1955 NBS

1950 NPL

1952 NBS

1952 NBS

1952 NPL

1953 BIPM

1953 NPL

1955 NBS

Average NPL

NBS except 1951

Ratio NBS unit to NPL unit

Group Ratio to BIPM

NBS 2288 1.019

M 1.000

" l.oiU

* .998

" 1.016

199 39 1.008

w 1.017

H 1.019

" 1.007

« 1.000

“ 1.006

“ 1.010

1,009

1.016

1.007

From table IV it is evident that the 1951 results did not represent

the NBS unit. From table I the average of the NPL values for the NPL

300-watt lanps, group 199 39, is 1*231 lumens, the NBS average is 1*195

lumens, and the BIPM value is 1*260. These values give 1.007 for the NPL

unit and 1.015 for the NBS unit, relative to the BIPM 1952 unit. Similarly

the data of table IV for the NBS 2288 group give values of 1.011* and 1.018

for the NPL and NBS units respectively relative to the BIPM 1952 unit if

the NBS 1951 results are excluded.

THE NATIONAL BUREAU OF STANDARDS

Functions and Activities

The functions of the National Bureau of Standards are set forth in the Act of Congress, March

3, 1901, as amended by Congress in Public Law 619, 1950. These include the development and

maintenance of the national standards of measurement and the provision of means and methods

for making measurements consistent with these standards; the determination of physical constants and properties of materials; the development of methods and instruments for testing materials,

devices, and structures; advisory services to Government Agencies on scientific and technical

problems; invention and development of devices to serve special needs of the Government; and the

development of standard practices, codes, and specifications. The work includes basic and applied

research, development, engineering, instrumentation, testing, evaluation, calibration services, and

various consultation and information services. A major portion of the Bureau’s work is performed

for other Government Agencies, particularly the Department of Defense and the Atomic Energy

Commission. The scope of activities is suggested by the listing of divisions and sections on the

inside of the front cover.

Reports and Publications

The results of the Bureau’s work take the form of either actual equipment and devices or published papers and reports. Reports are issued to the sponsoring agency of a particular project

or program. Published papers appear either in the Bureau’s own series of publications or in the

journals of professional and scientific societies. The Bureau itself publishes three monthly periodicals, available from the Government Printing Office: The Journal of Research, which presents

complete papers reporting technical investigations; the Technical News Bulletin, which presents

summary and preliminary reports on work in progress; and Basic Radio Propagation Predictions,

which provides data for determining the best frequencies to use for radio communications throughout

the world. There are also five series of nonperiodical publications: The Applied Mathematics

Series, Circulars, Handbooks, Building Materials and Structures Reports, and Miscellaneous

Publications.

Information on the Bureau’s publications can be found in NBS Circular 460, Publications of

the National Bureau of Standards ($1.25) and its Supplement ($0.75), available from the Superintendent of Documents, Government Printing Office. Inquiries regarding the Bureau’s reports and

publications should be addressed to the Office of Scientific Publications, National Bureau of

Standards, Washington 25, D. C.