General Information

Serial #

287949

Part Number

1

Total Parts

1

AKA

N/A

Patents

N/A

General Description

Metal (steel?) casing with glass covered gauge, paper scale, brass binding posts, and wood.

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

19.7 cm

Width

17.8 cm

Height

N/A

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Energy-electric

Category

Measurement

Sub-Category

N/A

Manufacturer

AKA

General Electric

Country

United States of America

State/Province

New York

City

Schenectady

Context

Country

Unknown

State/Province

Unknown

Period

Unknown

Canada

This is a typical DC ammeter used on switchboards in Canada in the 1920s and beyond. Designed for isolated plants or marine work, this type of ammeter had many possible places of use in Canada.

Function

To measure electric current.

Technical

The D8 is a magnetically shielded permanent magnet moving coil type of DC ammeter. This model of ammeter was constructed on the D'Arsonval principle and is designed for switchboard use. "They are neat in appearance, substantial in construction, and unsurpassed in accuracy" CGE catalogue. The D-8 model is smaller than the D-7 and is used where a compact instrument is needed. The very large opening for the screen allows in a lot of light and thus increases the visibility of the scale. Switchboards often had poor lighting, and even in good lighting conditions this kind of design feature could increase from how far away the operator could read the meter. As one operator needed to be able watch over a very large number of meters at one time, this was an important property.

Area Notes

Unknown

Details

Markings

Markings found on scale reads: "AMPERES/ GENERAL ELECTRIC CO./ SCHENECTADY, N.Y., U.S.A./ No. 287949 TYPE D8/ N.P. 6930-A PAT. JUNE 13, 1911" Number stamped on back: "282217 E"

Missing

N/A

Finish

Black finish with brass highlights.

Decoration

N/A