Design Scheme Of Ultrasonic Heat Meter

In this paper,the development of a ultrasonic heat meters based on ultrasonic sensors and high-precision platinum resistance temperature sensor,high-precision timing chip to achieve high-precision measurement of velocity,flow and heat,and fully tap the MSP430F4481 processor chip’s power consumption and computing precision measurement advantages of speed advantage and TDC-GP21 chip,developed by the calorimeter with low cost,high accuracy,ultra-low power consumption characteristics.In this article for ultrasonic heat meter research mainly includes the following aspects:(1)More in-depth analysis and comparison of several program flow measurement technology,about the use of transit-time ultrasonic flow sensor measuring principle applied in this study,describes considerations when applying this technique,a variety of factors that affect measurement accuracy.It describes the implementation of hardware design.(2)MSP430F4481 ultra-low-power control chip,temperature and flow measurement chip M-BUS interface chip TDC-GP21 TSS721A characteristics to explain in detail to compare a variety of common temperature sensors and transducers feature,according to the task functional design select the specific requirements of the temperature sensor and ultrasonic transducer model specifications.(3)Hardware and software design part calorimeter system to ensure the hardware circuit design low cost,low power consumption.Clarify the main design ideas presented and a list of components associated circuitry,for each circuit design were analyzed.Including flow temperature acquisition circuit,the master chip circuit,the slave M-BUS circuit,LCD display connection and simple buttons,etc.,the software part clarifies the low-power design and flow chart is given for each relevant module on software design and debugging of the platform and the mixed C and assembly language programming method were analyzed.(4)On this subject developed ultrasonic heat meter prototype detailed inspection of each index temperature,flow and other detailed testing,system average current 24.77uA.Test results consistent with "heat meter" industry standard requirements of Table 2,the built-in battery life of more than 10 years.Several indicators of this product in the domestic industry has a great advantage.