Embedded-based Instrumentation System for Electrical Resistivity Measurement on Conductive Concrete using Four-Electrode Method

摘要

Instrumentation system for testing of conductive concrete material using four-electrode method has been built. The system can measure material resistivity under the influence of voltage-injection variable, temperature changing in the characterization reactor, as well as the duration of the material characterization. The system uses an ACS-172 electrical current sensor, a DS-1820 temperature sensor to measure the temperature of the material, a SHT-11 sensor to measure the temperature and humidity of the material characterization reactor, and a DS-1307 RTC (Real-Time Clock) system for timing system and reference for controlling the duration of the material testing. The standard method of instrument for measure has been developed based on four electrode method. The system of instrumentation can be measured to numerical value of electrical conductivity and resistivity on material. This instrumentation system which has a heating reactor for the material sample, uses AVR-ATmega-128 as the controller element, and also has an computer interface to connect with LabVIEW-National Instrument. This system can be operated in dual-mode, that is automatic and manual mode. The automatic mode can be generated standard configuration based on computer connection (this part can be displayed a numerical data and real-time graph, and also has to recording/saving a numerical data), whereas manual mode only displayed of data without computer connection. The system of instrument has been developed to measure of electrical resistivity/conductivity, temperature and humidity in reactor, electrical current injected, voltage injection and voltage load on sample, and also setting of real-time date/time for automatic control process of characterization with variation of voltage injection, temperature/humidity, and time for material characterization process.