Renseignements généraux

Nº de série

1666873

Nº de partie

4

Nombre total de parties

12

Ou

S/O

Brevets

S/O

Description générale

metal casing and terminals/ synthetic top

Dimensions

Remarque : Cette information reflète la taille générale pour l’entreposage et ne représente pas nécessairement les véritables dimensions de l’objet.

Longueur

9,5 cm

Largeur

5,0 cm

Hauteur

17,4 cm

Épaisseur

S/O

Poids

S/O

Diamètre

S/O

Volume

S/O

Lexique

Groupe

Énergie-électrique

Catégorie

Mesurage

Sous-catégorie

S/O

Fabricant

Ou

Leeds Northrup

Pays

United States of America

État/province

Pennsylvania

Ville

Philadelphia

Contexte

Pays

Canada

État/province

Ontario

Période

Inconnu

Canada

An instrument used in the Calibration Unit of the Instrument Division of the Meteorological Branch of the Department of Transport of the Government of Canada. The Meteorological Branch became the Atmospheric Environment Service in 1971 and so this instrument was probably manufactured before that date. Part of a large collection of meteorological instruments acquired from the Meteorological Service of Canada (previously Atmospheric Environment Service) by the CSTM since 1967. MSC is the government agency responsible for collecting and disseminating meteorological data and forecasts in Canada. It was founded in 1871 in Toronto where it is still headquartered. The MSC was originally on the University of Toronto downtown campus but moved to Downsview in 1971 on land owned by UofT. The headquarters houses laboratories, research facilities and calibration and instrument maintenance facilities (now largely contracted out).

Fonction

A standard resistor is a resistor adjusted with high accuracy to a specified value, is little affected by variations in temperature and is substantially constant over long periods of time; this instrument was used in a meteorology instrument calibration unit to calibrate digital meteorological instruments such as barometers and thermometers.

Technique

An example of a standard resistance used for calibrating instruments. Leeds and Northrup's 1940 and 1946 catalogues list resistance model numbers 4020 to 4040 National Bureau of Standards type resistors, described as primary standards of resistance (Refs. 1-2). The 2030-B to 4045-B resistors would have been introduced at a later date. This type of resistance has four terminals with the heavy outer current terminals connected into the circuit and the lighter, inner terminals used to measure the potential drop. The resistance coils are mounted in oil in hermetically-sealed metal cases (Ref. 3).

Notes sur la région

Inconnu

Détails

Marques

incised white lettering on top reads '10000 OHMS/ CAT. 4040-B/ LEEDS & NORTHRUP CO./ PHILA, PA. MADE IN U.S.A./ 1666873'

Manque

appears complete

Fini

grey painted casing with plated parts/ black synthetic

Décoration

S/O