Online Monitoring of Electric Power Box Using Waveguide Sensors

Majority of the industrial and domestic fire accidents occur due to electric short circuits. Hence, it is imperative to monitor the condition of electric power box to facilitate preventive maintenance. The key reasons for power box failure are overheating, tripping, and arcing/sparking at the electric joints. This paper reports on the online condition monitoring of electric power box using the waveguide sensing technology. The critical components of the power box are monitored, namely; Miniature Circuit Breaker (MCB), Solid State Relay (SSR), and Contactor. A pair of wire waveguides is designed to monitor overheating as well as the occurrence of tripping in the MCB. While one waveguide functions as an active ultrasound temperature sensor, the other acts as a passive acoustic emission based arcing sensor. During the overheating experiments, the ultrasound sensor precisely measures the temperature gradient along multiple points on the sub-components, with a minimum gauge length of 10–15mm. The perturbation caused due to MCB tripping is successfully captured by the passive acoustic emission sensor and the location of tripping is determined. Both the overheating temperature and tripping signature are detected by the waveguide transducer system. This work has potential application in industrial and commercial establishments to ensure improved reliability and workplace safety.

RANCANG BANGUN SISTEM PEMUTUS ARUS SEBAGAI PENGAMAN TEMPERATUR BERLEBIH PADA INKUBATOR BAYI

Several countries in the world, including Indonesia, have reported baby-care accidents in the baby incubator due to the failure of the temperature control system to maintain a stable temperature. Therefore, this study reports the design of an circuit breaker system as an over-temperature safety in a baby incubator. Experimentally, the prototype consists of hardware design, software design, and testing system design. The hardware design has four main part, sensing layer using PT1000 as a temperature sensor, data processing layer using an ESP32 microcontroller, a circuit breaker system using a solid-state relay as an electronic switching, and LCD as a display. System testing has been done by evaluating the temperature readings on a prototype against the HTC-02 digital thermometer instrument and carried out in the electromedical engineering laboratory. The results show the accuracy of the temperature parameter is 99% and the circuit breaker system is able to cut the current from the power supply to the appliance when the temperature is more than 39°C which is indicated by an incandescent lamp "off" where this is equivalent to a heater at the baby incubator is in the "off" condition. From the results of this test, it can be concluded that the circuit breaker system as a safety over temperature in the baby incubator has functioned according to the design.Recommended the development of this prototype needs to be followed up by testing on low-tech baby incubators available at basic health care facilities so as to improve technology readiness to be effective in the community.

Design and Construction of an Automatic Home and Office Power Control System

In homes and offices, it is very common for occupants to forget to switch OFF the lighting and fans when leaving the premises. This can be attributed to human forgetfulness and the epileptic power supply which causes interruption that results in users forgetting the state of their appliances (whether they are ON or OFF). Consequently, these appliances would continue to work whenever power is restored when the occupants might have vacated the premise. This action is not a small contributor to energy wastage in a country like Nigeria where there is an inadequate energy supply to go round the populace. In this work, a simple but robust automatic home and office power control system is developed to auto-detect the presence of an occupant in the room through the passive infrared (PIR) sensor and control the electrical appliances (lighting and fan source) in the room. Certain conditions must be met for the operation of lighting and the fan source. The lighting comes up when the PIR sensor senses the presence of an occupant and the room is in darkness, while the fan would work when there is an occupant and the temperature in the room is above 35°C. These conditions are programmed to suit the need of the occupant but cannot be changed by the user. The device automatically switches off within five minutes after the last occupant leaves the room. Keywords— Microcontroller, Passive infrared (PIR) sensor, Solid State Relay (SSR), and Switching

Design and analysis of a light electric vehicle

This paper discusses a systematic vehicle design process in which light weight is taken as the vehicle design objective, and the designed frame is analyzed in detail. The load condition of a vehicle under different circumstances is calculated according to the distances from the front and rear wheels to the centroid position. The stress on the components in the condition is analyzed by finite element analysis, the steering geometry of the vehicle is analyzed, and the vehicle's turning angle and radius are designed. The displacement of the vehicle under a load is calculated by rigidity analysis to determine the stability of the vehicle in motion. The experimental modal analysis of the real frame and the finite element method are verified mutually for the electric vehicle body-in-white (BIW) manufacturing process to determine the consistency of model formation and the real frame. In terms of the circuit design, we used no-fuse switches and fuses to provide overcurrent protection for the main power supply, and the chip is combined with an optically coupled circuit and current sensor, which is driven by a restriction controller for protection. Moreover, a solid-state relay (SSR) is used for current protection and for controlling the forward/reverse rotation of the motor.

A Low-Cost Temperature-Controlled Chamber Fabricated for Materials Testing

This paper presents a low-cost temperature-controlled chamber based on the natural radiation principle. The temperature-controlled chamber assembled using a 1.0 mm thick aluminum sheet equipped with expanded polystyrene lagging material, temperature controller, K-type thermocouple and solid-state relay. A high precision temperature sensor (K-type thermocouple) attached to the sample under test (SUT) near the instrument’s measuring point gives a feedback signal to the temperature integrated derivative (TID) controller. The accuracy of temperature readings from the chamber investigated and the chamber itself, calibrated with temperature sensor by Fluke, show temperature readings that correspond to the set temperature values. In addition, perovskite thin film deposited on a glass substrate of 75 × 25 mm was tested and the temperature readings equally correspond to the temperature set values. This low-cost and low-energy-consumption chamber could use in laboratories in the developing world where there is scarce power supply.

Rancang Bangun Sistem Kendali Kecepatan Putar Motor DC menggunakan PID Controller pada Mesin Pengaduk

Kegiatan pengadukan bahan-bahan pertanian menjadi berbagai macam produk pangan ataupun non pangan membutuhkan mesin pengaduk. Mesin pengaduk dalam penelitian ini memiliki masalah saat digunakan yaitu bahan yang diaduk melumpah dari wadah, suara yang dihasilkan berisik dan motor cepat panas. Penelitian ini bertujuan untuk menghasilkan sistem kendali yang baik pada mesin pengaduk agar dapat meningkatkan kinerja dari mesin pengaduk. Metode yang dilakukan yaitu perancangan sistem perangkat keras dan perangkat lunak. Sistem perangkat keras menggunakan komponen mikrokontroler, Solid State Relay (driver motor), Motor DC (aktuator), rotary encoder (sensor) dan power supplay (sumber tegangan) sedangkan sistem perangkat lunak berisi algoritma bahasa program kendali PID. Prinsip kerja sistem yaitu lup tertutup dimana kecepatan motor akan terbaca oleh sensor dan diinformasikan ke mikrokontroler untuk membandingkan dengan kecepatan yang diinginkan, kemudian memperbaiki kesalahan yang terjadi. Berdasarkan hasil tuning dengan menggunakan metoda internal control (MIC) diperoleh konstanta PID sebesar Kp: 0.259, Ki:5.647 dan Kd: 0.200. Nilai konstanta yang diperoleh sudah dapat memberikan kestabilan pada berbagai kecepatan (62,130,190 dan 252 rpm). Pengujian kecepatan motor DC pada mesin pengaduk dengan mengunakan beban yaitu adonan roti dan kedelai menghasilkan kecepatan yang dapat mengikuti set point (kecepatan yang diinginkan) dan respon sistem menunjukkan settling time yang pendek, overshoot bernilai 0 dan nilai error steady state yang masih berada pada batas toleransi yaitu 2% atau 5%.