Electrodynamic wattmeter with direct recording. It has a pointer equipped with a tracing tip, supporting the moving equipment. It turns out to be the first example in the world of a recorder with automatic force balancing.
INSIGHTS
The disposition of the ammeter-like and volumetric coils is comparable to the one of a Lord Kelvin’s scale. The antagonistic pair has an elastic nature and the presence of dampers makes the motion of the pointer similar to the one of an ammeter. The unique geometric configuration of the mechanic device allows to amend the trace, that based on the motion of the moving equipment should develop according to an arch of a circle. The ammeter-like range of the tool is of 85A and the volumetric one of 1,3Kg.
The recording gear is made up of a roller system, placed in rotation with a clockwork mechanism activated by a spring, charged electrically, that drags a roll of paper divided into millimeters and a diagram allowing them to pass under the nib.
In 2001 the tool underwent a CESA restoration, carried out by Gregorio Chiarenza of the Elettrotechnics Department.
Technical Data Sheet
Name: Watmeter recorder
CategoryWattmeter recorder with automatic balancing with a Lord Kelvin’s scale equipment
Manufacturer: Westinghouse Electric & Manifacturing Co. Pittsburgh, USA
Year of production: 1914
Dimensions: 330×400×230
