ANALISIS HUBUNGAN BESARAN FISIKA PADA SISTEM KONTROL TEMPERATUR DENGAN SENSOR PTAT TIPE IC LM 35 BERBASIS MIKROKONTROLER AT89S51

Abstract

ABSTRACT

Temperature control system is an important instrument to control temperature of an object at set point. Objectives of this research was to investigate the relation between physical quantities in temperature control system. Instruments that used to collect the data were digital thermometer and universal digital multimeter. The data analysis in research were graph method and error theory. Result of data analysis indicate that: 1). Output voltage of LM 35 sensor is directly proportional to the temperature with 0.01 volt/^oC sensitivity and 0,003 volt initial voltage, 2). final output voltage of two non inverting amplifier is directly proportional to the temperature with 0.0485 volt/^oC gradient and 0.032 volt initial voltage, 3). numbers that displayed at seven segment can varied from 0 until 250 for temperature variation from 0 until 100^o C before linearization and the numbers that displayed at seven segment were match by measured temperature value after linearization, 4). output voltage  of relay switching circuit and SCR gate voltage are high for temperature is lower than set point temperature and are low for temperature is higher than set point temperature.

Keywords: control system, temperature controller, PTAT sensor, physical quantities, microcontroller