Penelitian ini bertujuan melakukan studi perbandingan arus awal pada perangkat elektonik tanpa pemasangan soft start dan dengan pemasangan soft start serta mengetahui pengaruh resistor penahan arus terhadap harga arus listrik. Metoda penelitian dilakukan dengan uji coba rangkaian soft start pada beban uji 650 watt. Variabel penelitian ini diantaranya yaitu rangkaian soft start, tegangan listrik PLN 220 volt dan beban uji 650 watt sebagai variabel kontrol, resistor penahan arus berupa resistor keramik sebagai variabel manipulasi dan variabel responnya berupa nilai kuat arus awal dan tegangan awal yang diukur bersamaan menggunakan multimeter dan tang ampere. Hasil penelitian yang diperoleh menunjukkan bahwa rangkaian soft start yang telah dibuat mampu mengurangi lonjakan arus awal pada beban uji 650 watt. Arus yang tercatat tanpa soft start yakni 3,40 A, sementara ketika soft start terpasang arus tereduksi mencapai 50%. Semakin besar nilai hambatan resistor penahan arus, maka arus awal yang tereduksi semakin besar. Resistor 47 Ω mampu mereduksi arus awal paling besar namun kurang baik bagi beban uji 650 watt karena saat tegangan stabil, nilai yang terukur kurang dari 220 volt. Maka dari itu, hambatan 39 Ω disarankan untuk beban uji 650 watt karena nilai tegangan saat stabil mencapai 220 volt sesuai kebutuhan beban uji.
Kata kunci: soft start, start current, resistor
This study aims to conduct a comparative study of the start current on electronic devices without the installation of soft start and by installing soft start and to know the effect of current resistors on the value of electric current. The research method was carried out by testing the soft start circuit at 650 watt test loads. The variables of this study include the soft start circuit, the electricity voltage of 220 volts and the test load of 650 watts as the control variable, current holding resistors in the form of ceramic resistors as the manipulation variable and the response variable in the form of start currents and start voltages measured together using multimeters and pliers ampere. The results obtained show that the soft start circuit that has been made can reduce the initial inrush current at a 650 watt test load. The current recorded without a soft start is 3.40 A, while when a soft start is installed the reduced current reaches 50%. The greater the value of the resistor current holding resistor, the reduced start current is greater. The 47 Ω resistor can reduce the largest initial current but is not good for the 650 watt test load because when the voltage is stable, the measured value is less than 220 volts. Therefore, a resistance of 39 Ω is recommended for 650 watt test loads because the voltage when stable reaches 220 volts according to test load requirements.
Keywords: soft start, start current, resistor