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Title: Device and method for measuring the coefficient of performance of a heat pump

Abstract

A method and instrument is provided which allows quick and accurate measurement of the coefficient of performance of an installed electrically powered heat pump including auxiliary resistane heaters. Temperature-sensitive resistors are placed in the return and supply air ducts to measure the temperature increase of the air across the refrigerant and resistive-heating elements of the system. The voltages across the resistors which are directly proportional to the respective duct tempertures are applied to the inputs of a differential amplifier so that its output voltage is proportional to the temperature difference across the unit. A voltage-to-frequency converter connected to the output of the differential amplifier converts the voltage signal to a proportional-frequency signal. A digital watt meter is used to measure the power to the unit and produces a signal having a frequency proportional to the input power. A digital logic circuit ratios the temperature difference signal and the electric power input signal in a unique manner to produce a single number which is the coefficient of performance of the unit over the test interval. The digital logic and an in-situ calibration procedure enables the instrument to make these measurements in such a way that the ratio of heat flow/power inputmore » is obtained without computations. No specialized knowledge of thermodynamics or electrons is required to operate the instrument.« less

Inventors:
;
Publication Date:
OSTI Identifier:
6456540
Application Number:
ON: DE83010482
Assignee:
ERA-08-029812; EDB-83-085324
DOE Contract Number:  
W-7405-ENG-26
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 47 OTHER INSTRUMENTATION; COEFFICIENT OF PERFORMANCE; MEASURING INSTRUMENTS; HEAT PUMPS; AMPLIFIERS; CALIBRATION; DIGITAL CIRCUITS; FREQUENCY CONVERTERS; POWER METERS; RESISTORS; ELECTRIC MEASURING INSTRUMENTS; ELECTRICAL EQUIPMENT; ELECTRONIC CIRCUITS; ELECTRONIC EQUIPMENT; EQUIPMENT; METERS; 320100* - Energy Conservation, Consumption, & Utilization- Buildings; 440300 - Miscellaneous Instruments- (-1989)

Citation Formats

Brantley, V.R., and Miller, D.R. Device and method for measuring the coefficient of performance of a heat pump. United States: N. p., 1982. Web.
Brantley, V.R., & Miller, D.R. Device and method for measuring the coefficient of performance of a heat pump. United States.
Brantley, V.R., and Miller, D.R. Tue . "Device and method for measuring the coefficient of performance of a heat pump". United States.
@article{osti_6456540,
title = {Device and method for measuring the coefficient of performance of a heat pump},
author = {Brantley, V.R. and Miller, D.R.},
abstractNote = {A method and instrument is provided which allows quick and accurate measurement of the coefficient of performance of an installed electrically powered heat pump including auxiliary resistane heaters. Temperature-sensitive resistors are placed in the return and supply air ducts to measure the temperature increase of the air across the refrigerant and resistive-heating elements of the system. The voltages across the resistors which are directly proportional to the respective duct tempertures are applied to the inputs of a differential amplifier so that its output voltage is proportional to the temperature difference across the unit. A voltage-to-frequency converter connected to the output of the differential amplifier converts the voltage signal to a proportional-frequency signal. A digital watt meter is used to measure the power to the unit and produces a signal having a frequency proportional to the input power. A digital logic circuit ratios the temperature difference signal and the electric power input signal in a unique manner to produce a single number which is the coefficient of performance of the unit over the test interval. The digital logic and an in-situ calibration procedure enables the instrument to make these measurements in such a way that the ratio of heat flow/power input is obtained without computations. No specialized knowledge of thermodynamics or electrons is required to operate the instrument.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1982},
month = {5}
}