A RESISTANCE THERMOMETER FOR TRANSIENT TEMPERATURE MEASUREMENTS.

Abstract : A 0.000025 inch diameter, 90% platinum-10% rhodium wire was evaluated as a resistance thermometer. From steady state evaluation of the wire's physical properties, the transient response of the wire was predicted. The predictions agree well with measured time constants for the wire. The bare wire with a detection current of 0.1 milliamps will have a sensitivity of approximately .07 millivolts per degree F. The frequency response of the wire in still air is 3200 cycles per second and this increased to approximately 6000 cycles in a moving air stream of 100 feet per second. (Author)