D.C. Ammeter


Accession Number: 2009.ph.163


The Direct Current Ammeter is mounted on a wooden base with a wooden backboard. At the top of the face is a scale calibrated in amperes, ranging from 0-1.0. Under the scale is written “USE WITH EXTERNAL SHUNT”. On the back of the ammeter is a light bulb socket, minus the light, ostensibly meant to light the scale face. To either side of the socket are two terminals, labeled “Positive” and “Negative” respectfully, with non-production labels. There are also four distinct sets of terminals on the very back of the ammeter, with labels reading “1 AMP., 5 AMP., 10 AMP., and 20 AMP., respectively. Each terminal (except for the 20 AMP. terminal) has an additional metal plaque indicating amperage and what model it is to be used with.

Alternative Name: Direct Current Ammeter

Primary Materials: Wood, Metal, Glass


Old inventory number = phy1026A-B. The face of the ammeter reads “WESTON STATION AMMETER, NO. 10870”, “Made By WESTON ELECTRICAL INSTRUMENT CO., NEWARK, N.J., U.S.A.”. The face also has a small plate with patent information.

Dimensions (cm): Height = 36, Width = 33, Length = 24


Measuring amperage in electrical circuit; possibly a demonstration device


Good. The metal is corroded in places. The wood backboard is marked and nicked. The glass of the scale is cracked in half.

Associated Instruments:


Weston Electrical Instrument Company, Newark, New Jersey, USA.

Date of Manufacture: Early 20th Cent.


University of Toronto Department of Physics

Historical Notes: