A Method of Measuring Temperature at a Distance by Electrical Means.

Abstract

Abstract 11,765. Crawley, C. W. S., and Trotter, A. P. May 23. Thermometers.-In an apparatus for measuring and indicating temperature at a distance electrically, a Wheatstone bridge a, b, c, d is exposed to the temperature to be measured. The bridge has four coils of equal resistance at 0‹ C., but adjacent coils are composed of metals or alloys having different temperature coefficients, such as copper and german silver or iron and maganin. Two opposite junctions are connected to a battery or other source of electricity, and the other junctions are connected to a galvanometer calibrated to read temperature. Three temperature-measuring bridges and a testbridge m are shown adapted to be thrown into action singly by switches l, l*. The current may be taken from an electric lighting circuit, the main current being passed through a bridge consisting of a number of sections k, k*. The Wheatstone bridges are connected to the ends of the section k*, a switch n being provided to adjust the current when the test bridge m is in action. The sections k are made of german silver, and the section k* and the galvanometer coil of copper or other materials arranged to give a constant current as their temperature varies.

Inventors

• 👤 Charles William Scott Crawley
• 👤 Alexander Pelham Trotter

Bibliographic Details