Now showing 1 - 2 of 2
  • Publication
    Validation of Electrical Noise of a DC Motor through Controlled Varistor Cracking: An Experimental Study
    The varistor is an electronic component that protects the DC motor's circuitry from electrical noise or transients that can cause damage. It works as a voltage-dependent resistor that can change its resistance according to the applied voltage. Once the voltage surpasses a specific threshold, the varistor conducts and directs the excess voltage away from the motor's circuitry. In small DC motor manufacturing, ring varistors are vital for reducing electrical noise, minimizing spark-induced damage to the commutator and brush, and extending the motor's lifespan. Additionally, they prevent damage to electronic parts in the customer's mechanism set. The objective of this study is to investigate the impact of varistor cracks or chips that may occur during the soldering process of varistors to the commutator. To confirm the occurrence of cracks or chips, intentional damage will be inflicted on the varistors. The study aims to determine how the presence of cracked or chipped varistors affects the electrical noise produced by a DC motor during its operation. The resulting spark was observed through an oscilloscope, and it was found that the effect could be substantial, up to 5 to 10 times the rated voltage supplied to the motor. In the next phase of this study, further tests will be conducted on motors without varistors to provide a comparison.
  • Publication
    Temperature Distribution Analysis of Lithium-Ion Polymer Battery Surface
    The main objective of this study is to investigate the heat load generated by the Lithium-ion (Li-ion) battery during the completion of the cycle. Besides that, the objective is also to identify the most affected surface of the Li-ion battery towards the temperature during the charging and discharging process. An experiment is carried out for five different conditions of battery to obtain the data for heat load calculation purposes. The five conditions are differences in discharge ampere. From the result obtained there are differences in heat load generated by the battery during the charging and discharging process for every condition. Furthermore, the greater the discharge ampere, the lower the time taken for the battery to discharge and the higher the heat load generated by the battery. Besides that, an experiment to investigate the temperature distribution along the experiment is also carried out. Four surfaces of battery (front, right, left, back in vertical position of battery) are put into concern in obtaining the temperature distribution. Every surface gives a different temperature distribution during the experiment. Surface 4 recorded the highest average temperature distribution. Thus, the cooling system will consider the cooling capacity at this surface.