ANALISIS TAHANAN ISOLASI PADA ISOLATOR PORSELIN DAN POLIMER TERHADAP POLUTAN GARAM DI GISTET 500 KV ADIPALA CILACAP
Authors: Darmadi Agam Celvano , Kholistianingsih Kholistainingsih , Yulianto Priyono 
Published: July 2023

GISTET 500 kV Adipala is one of the locations that is in the spotlight in the Central Java Transmission

Main Unit (UIT JBT) because of frequent pollutant problems, especially during the dry season. This causes

the surrounding air to have a high salt content and also the flyash from the PLTU. This condition causes

the insulators on the tower and gantry to be exposed to pollutants and can result in flashover and

breakdown. This study discusses the effectiveness of polymer insulators by testing the insulation resistance

of clean porcelain insulators, polluted porcelain, clean polymers, and polluted polymers. To get the

condition of the insulator polluted with salt water, the method of raining on the insulator is carried out.

The result of the clean porcelain test was 2970 GOhm. in the experiment with polluted porcelain insulators,

the following results were obtained: the minimum 50ml experiment measured a resistance value of 2950

GOhm, which was reduced by 1% from the clean one and the maximum 500ml experiment measured the

resistance value to 390,3 GOhm, which was 87% reduced from the clean one. The net polymer insulator test

results are 3222.8 GOhm. In the experiment with polluted polymer insulators, the following results were

obtained: the minimum 50ml experiment measured a resistance value of 2982 GOhm, which was 7% less, the

maximum 500ml experiment was 2382.8 GOhm, 26% less. From the results of these experiments, it can be

seen that in the porcelain insulator experiment with salt water polluted, the insulation resistance value

decreased in each experiment until the maximum experiment was 500ml which obtained a resistance value

of 390.3 GOhm. The results of the clean polymer insulator test were 3222.8 GOhm, while the pollutant polymer

insulator experiment recorded a value that was not significantly decreased with the lowest value in the

500ml experiment of 2382.8 GOhm. When compared with the minimum standard of insulation resistance for

the 500 kV system used by PLN is 500 MOhm. Porcelain insulators that experience continuous exposure to

pollutants have the potential to experience flashover and faster breakdown compared to polymer insulators

when viewed from the trend of decreasing insulating resistance. It can be concluded that polymer insulators

are more effective for use in environments that have a high level of exposure to air pollution such as at

GISTET Adipala.

Keywords: Porcelain Insulator, Polymer Insulator, Pollutant, Flashover, Breakdown

GISTET 500 kV Adipala adalah salah satu lokasi yang menjadi sorotan di Unit Induk Transmisi Jawa

Bagian Tengah (UIT JBT) karena seringnya masalah polutan terutama pada musim kemarau. Hal ini

menyebabkan udara sekitar memiliki kandungan garam yang tinggi dan juga flyash dari PLTU. GISTET

Adipala. Hal ini menyebabkan isolator pada tower dan gantry menjadi terpapar polutan dan dapat

mengakibatkan terjadinya flashover dan breakdown. Oleh karena itu diperlukan analisis efektifitas isolator

polimer dengan cara melakukan pengujian tahanan isolasi terhadap isolator porselin bersih, porselin

berpolutan, polimer bersih, dan polimer berpolutan. Untuk mendapatkan kondisi isolator berpolutan air garam, dilakukan metode penghujanan ke arah isolator. Hasil pengujian porselin bersih tercatat 2970 GOhm.

pada percobaan isolator porselin berpolutan didapat hasil sebagai berikut: percobaan 50ml, terukur nilai

tahanan sebesar 2950 GOhm, yaitu berkurang 1% dan percobaan 500ml terukur nilai tahanan sebesar 390,3

GOhm, yaitu berkurang 87%. Untuk hasil pengujian isolator polimer bersih sebesar 3222,8 GOhm. 50ml terukur

nilai tahanan sebesar 2982 GOhm, yaitu berkurang 7%, 500ml yaitu sebesar 2382,8 GOhm, berkurang 26% dari

yang bersih. Dari hasil percobaan tersebut dapat dilihat pada percobaan isolator porselin berpolutan air

garam adalah nilai tahanan isolasi yang menurun pada tiap percobaan hingga percobaan paling banyak yaitu

500ml yang diperoleh nilai tahanan 390,3 GOhm. Hasil pengujian isolator polimer bersih sebesar 3222,8 GOhm,

sementara percobaan isolator polimer berpolutan tercatat nilai yang tidak begitu turun dengan nilai paling

rendah pada percobaan 500ml sebesar 2382,8 GOhm. Jika dibandingkan dengan Standar minimal tahanan

isolasi untuk sistem 500 kV yang digunakan PLN adalah 500 MOhm. Isolator porselin yang mengalami

paparan polutan secara terus menerus berpotensi mengalami flashover dan breakdown lebih cepat

dibandingkan dengan isolator polimer jika dilihat dari trend penurunan tahanan isolasinya. Dapat

disimpulkan bahwa Isolator polimer lebih efektif untuk digunakan pada lingkungan yang memiliki tingkat

paparan polusi udara yang tinggi seperti di GISTET Adipala.

Kata Kunci: Isolator porselin, Isolator Polimer, Polutan, Flashover, Breakdown