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Pada jaringan listrik 3 fasa perlu dilakukan monitoring besaran listrik yang meliputi tegangan (V), arus (A), faktor daya (Cos θ), daya (W) dan konsumsi energi (kWh). Hal tersebutdilakukan untuk mengetahui perubahan besaran listrik terhadap waktu, sehingga dapat diketahuikualitas pasokan energi listrik pada sistem, dapat diketahui jika terjadi gangguan dan dapatdiketahui besar konsumsi energi listrik secara berkala. Untuk pengukuran tegangan digunakan trafo step-down sebagai sensor tegangan,pengukuran arus digunakan sensor arus ACS712-30A dan pengukuran konsumsi energidigunakan kWh meter merk Thera tipe TEM015-D4250. Sedangkan nilai daya didapat dariperhitungan, dimana daya merupakan hasil bagi antara nilai konsumsi energi terhadap waktu.Ketika nilai tegangan, arus dan daya diketahui maka nilai faktor daya juga dapat dihitung karenanilai daya merupakan hasil kali dari tegangan, arus dan faktor daya. Untuk pemrosesan datapengukuran dan perhitungan dibuat pemograman python dengan menggunakan Single BoardComputer BCM2835 atau biasa dikenal dengan sebutan Raspberry Pi.  Hasil penelitian ini menunjukkan bahwa alat ukur tegangan, daya dan faktor daya yangdigunakan memiliki tingkat presisi yang sesuai dengan standar IEC No. 13B-23, namun untuk alatukur arus belum memenuhi standar tetapi masih dapat digunakan karena memiliki selisihpengukuran yang kecil jika dibandingkan dengan hasil pengukuran menggunakan alat ukur yangada di laboratorium. Dengan menggunakan Raspberry Pi, data hasil monitoring berhasil disimpanpada database dan dapat dilihat dari WEB dalam bentuk grafik.Kata kunci : Jaringan listrik 3 fasa, sensor tegangan, sensor arus, kWh meter, Raspberry Pi.

No abstract

This paper proposes a method of detecting air pollution in a region using image processing techniques. The image used is the infrared image that obtained using a modified digital camera by mounting the SRS filter. Image processing technique used is to utilize wavelet transformation. Pollutants are detected based on the average number of white pixels that appear on the image. This white pixel appears due to the reflection of the wavelength of the pollutant that hits the sensor on the camera. From the results of the proposed method detection is known that the highest pollution occurs in 12.00 which is the busiest traffic time and the lowest pollution occurred in 08.00 where the traffic passing through the area has not been crowded.

The objective of the study is to calculate and analyze the pollution load capacity of the specified river segment using combination of the water quality model "QUAL2Kw" and Geographic Information System (SIG). Location of the study is Pesanggrahan river in the Depok City sections. The result of modeling shows that the actual pollutant load discharged to the river section for BOD, COD and TSS are 8.257; 59.930 dan 48.975 kg/days, respectively. Meanwhile the allowable pollutant load or the pollution load capacity of the section of the river for those pollutant parameters are 8.111, 58.20; 49.085 kg/days, respectively. It indicates that the pollution load capacity of the section of the river has been exceeded that needs reduction as much as load of 146 kg/days for BOD, 1,650 kg/days for COD and 110 kg/days for TSS in order to to meet the set water quality standard of the river section. The coefficient of determination (r 2) of 0,99 for BOD and COD and 0,998 for TSS indicates that the modelled concentration of BOD, COD and TSS and those concentration of measured results show the strong relationship and the low value difference. In addition, the calibration of modeling results have an error rate of less than 10% indicated by the value of RMSE of 0.065, 0.09, 0.2 for BOD, COD and TSS, respectively. The error value shows that the water quality modeling results can be used for predicting the pollution load capacity or the allowable pollutant load of the river section