Study On Uncertainty Of Measurement In Point Type Heat Fire Detector's Basic Function Test

Measurement is indispensable in industrial and agricultural production,science and technology,trade,engineering projects and daily life,the purpose of which is to get the true value of the measured things.However,the true value is uncertainy due to the error,thus the measured result can be only represented by the approximate estimate of true value and an approximate error range.Measurement uncertainty theory was put forward and developed in the 1960 s,and was widely used in various fields like quality management and metrology,etc.With international trade developing,the quality of the testing data needs to be mutual verified,matched and recognized.One basic premise of uncertainty application is to make reasonable evaluation of measurement uncertainty.On one hand,if the evaluation of uncertainty is too large,unnecessary investment to buy more expensive testing instrument may come into being because people think the existing measuring level cannot meet the need,or else,people may have some suspicious and interference of calibration laboratory service job,one the other hand,if evaluation is too small,the calibrating requirement will be harsh,it may make the enterprise economic losses,etc.Fire electronic products are main detected in the laboratory,due to the importance of measurement uncertainty,the writer will use point type heat fire detector as sample to show the test progress of measurement uncertainty,it is based on some relative requirements and national testing standards GB 4716-2005 "point type heat fire detectors" to study the basic functions like act temperature and response time.First of all,classify components which may cause uncertainty,confirm the sources of uncertainty and determine the calculation formula.the sources of uncertainty of response time cover repeatability,alarm process,personnel practice,a to measure error and resolution of stopwatch.The sources of uncertainty of action temperature cover the repeatability,the uniformity of air temperature in the oven,temperature fluctuations in the oven,indication error and measurement resolution of measuring instrument.Secondly,carry out the position test to check out the influence about airflow direction to the detectors,then ensure the maximum and minimum response time orientation of sample.Choose the minimum response time orientation to go ahead the basic functional test,each item of which will be tested 10 times by the same professional staff.The data is recorded as uncertainty components of repetitive.Then compound each uncertainty components to get the uncertainty report.At last,MATLAB is combined with the Monte Carlo Method to produce a series of simulation value,by calculating the simulation value of standard deviation,the verification value of measurement uncertainty evaluation can be got.In this way,people can understand the quality inspection ability more easily and transparency.