Weston AC portable test instrument model 155

Weston AC portable test instrument of dimensions 180 x 170 x 82 mm / 7.1 x 6.7 x 3.2 inch. Instrument is in a tabletop shaped wooden box with a leather handle on the right side. In the center of the box is an engraving of the manufacturer titled "Weston Electrical Instrument Corp, Newark, NJ, USA", Model 155. Front view.

Figure 1: Weston AC portable test instrument model 155. Front view.

Weston AC portable test instrument of dimensions 180 x 170 x 82 mm / 7.1 x 6.7 x 3.2 inch. Instrument is in a tabletop shaped wooden box with a leather handle on the right side. In the center of the box is an engraving of the manufacturer titled "Weston Electrical Instrument Corp, Newark, NJ, USA", Model 155. Front corner view.

Figure 2: Weston AC portable test instrument model 155. Front corner view.

This is an AC voltmeter made by the Weston Electrical Instrument company in the 1920’s. This instrument has the serial number of 77139. There were many different variations made of the 155 model for both voltage and current in different ranges. This particular instrument is a 0-150 milliampere single range model for 25-500 cycles. These are laboratory grade instruments with 0.5 to 1 % accuracy. AC voltmeters are used to measure the electrical currents in an AC power source. This instrument would have been used in the physics laboratories at KU.

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