Permasalahan yang kerap terjadi umumnya pada motor induksi di PLTU yaitu menemui berbagai kerusakan termasuk halnya pada Motor Circulating Water Pump(CWP). Hal tersebut disebabkan karena adanya kegagalan tahanan isolasi terhadap kumparan atau belitan di stator motor serta penurunan polaritas index yang dipengaruhi oleh kelembaban, cuaca, suhu ruangan maupun lingkungan area motor tersebut berada, serta lamanya waktu pengoperasian dari motor tersebut. Mengingat Motor CWP tersebut dioperasikan secara terus menerus, maka dibutuhkan kegiatan pemeliharaan secara berkala yang bertujuan untuk menjaga kualitas dan keandalan operasi motor tersebut serta mencegah terjadinya kegagalan atau kerusakan peralatan secara tiba-tiba. Parameter isolasi dan polaritas index didapat melalui hasil pengujian tahanan isolasi dan polaritas index guna mengetahui kondisi dan kualitas isolasi dari motor yang diuji, memastikan nilainya sesuai dengan standar yang ditetapkan yaitu sesuai dengan standar IEEE:43-2013, serta menentukan perawatan yang tepat untuk mencegah terjadinya kegagalan isolasi ketika motor beroperasi yang dapat menyebabkan short circuit, ground fault, dan timbulnya arus bocor.

The problem that often occurs generally in induction motors at PLTU is that they encounter various damages, including the case of the Circulating Water Pump (CWP) Motor. This is due to the failure of the insulation resistance to the coil or winding in the stator of the motor and a decrease in the polarity index which is influenced by humidity, weather, room temperature and the environment where the motor is located, as well as the length of operating time of the motor. Considering that the CWP motor is operated continuously, periodic maintenance activities are needed which aims to maintain the quality and reliability of the motor operation and prevent sudden equipment failures or damage. The parameters of insulation and polarity index are obtained through the results of testing the insulation resistance and polarity index in order to find out the condition and quality of insulation of the motor being tested, ensure that the value is in accordance with the established standards, namely in accordance with the IEEE:43 2013 standard, and determine the appropriate maintenance to prevent insulation failures when the motor is operating which can cause short circuits, ground faults, and the onset of leakage currents.