Battery Resistance Measurement with a Digital Multimeter: An Electrical Tech Experiment - , Lab Reports of Humanities

Download Battery Resistance Measurement with a Digital Multimeter: An Electrical Tech Experiment - and more Lab Reports Humanities in PDF only on Docsity! Exploring Electrical Technology (IDST 300) Messiah College Dr. Harold Underwood Experiment #2: Measuring the Battery’s Hidden Resistance with a Digital Multimeter (DMM) Objectives: 1. Learn how to use a Digital Multimeter to measure DC voltage and current. 2. Find the internal resistance of various batteries. 3. Note the special applications for batteries of a certain type. Introduction: DC Battery Measurements with a DMM Electricity finds application in almost all technology we use today. Devices ranging from the simple light bulb to the most sophisticated personal computer rely on proper connections of the electrical circuitry and a voltage source such as a battery or equivalent. Understanding electricity can seem difficult since we cannot “see” electricity directly; we can only see its effects. In this experiment, you will make some measurements that will hopefully improve your understanding of batteries and their practical use. Please work with a partner. Although this course assumes no prior knowledge of science or technology, some students in the class may have had previous experience with physics, physical science and/or electricity. Those of you who have had such experience can help perform and explain details of the procedure to your lab partner. Procedure: DC Battery Measurements with a DMM In this section, you will use an electronic meter to measure the DC voltage, current and calculate the internal resistance of three different batteries. You will use the Fluke 73 Digital Multimeter (DMM), so called since it can measure a variety of electrical quantities including DC or AC voltage, current and resistance. The word “digital” describes the nature of the output in the form of numbers, using a liquid crystal display (LCD) similar to a calculator, except larger. The DMM has become very popular compared to the more traditional analog meter that uses a needle to display its measurements. However, the analog meter still has certain advantages. We will use the DMM here for convenience. ____1. If not already attached, insert the plug end of the red lead into the red socket marked V  and the plug end of the black lead into the socket marked COM. ____2. Turn the dial of the DMM so that it points to V — symbol which stands for DC voltage. ____3. If OK, the meter should display .000 VDC. If not, please notify your instructor. ____4. Pick up your battery cell. Measure its open circuit voltage (Voc) by touching the black probe to the negative (-) contact of the battery and the red probe to the positive (+) contact.