Intellectual Precise Temperature Sensor with Wireless Interface

Abstract

Intellectual precise temperature sensor with wireless interface (ITWS) for contact measurements with absolute error of ±0.05 ◦C in the temperature range from 5 to 95 ◦C was developed. Platinum thin film resistance thermometer was used as the sensitive unit. High accuracy of measurements is supported by following. Investigations and modeling of temperature dependence of resistivity for sensitive unit allowed to develop mathematical model ensuring calculation of temperature with the error not exceeding 5× 10−3 ◦C. Original patented design, and hardware and software solutions for ITWS were developed. Method and mathematical models for thermocompensation of electronic components of ITWS were elaborated, which allowed sufficient decrease of measurement error during measurements and exploitation. Methodology, and hardware and software measuring system for individual ITWS calibration in automatic regime were developed, which include correction of mathematical model for the calculation of temperature for each sensor. ITWS has several design and technological solutions, and is developed for the temperature measurements of heat transfer agent in the pipelines of heating and hot water supply systems, independently of pipeline diameter. Measured data are transferred by radio channel to the recording and display devices. ITWS are used in automated systems for energy carrier controlling and determination of individual heat consumption. ITWS consists of following modules: sensitive unit, analog-to-digital converter, microcontroller, radio transceiver (carrier frequency is 434 or 868 MHz, output power of transmitter is not more than 10 mW), antenna and power supply (3.6 V).