Wattmeter for some common requirements

The paper describes the background requirements and development work leading to the production of a low cost static wattmeter for use in educational establishments. Initially it was envisaged that the new wattmeter would have some industrial applications and these aspects are described, although no development has been done as yet. The form of the paper follows the growth of the new wattmeter from initial specification to its developed form. The work has been controlled throughout by the need to produce a simple instrument, which, although not a complete replacement for the dynamometer type, can nevertheless be used in many circumstances where the precision and expense of the dynamometer is unnecessary.