In practice, the measurement of electrical quantities for commercial purposes, for example to measure consumption of electrical energy that has been used by the consumer (kWh-meter or kVAr-meter) can be done in two ways, namely direct measurement and indirect measurement.<\/span> Measurement is directly applied to the installation of small-scale low-voltage electricity.<\/span> In this case the measuring devices used directly connected to the load directly.<\/span><\/p>\n Measurements are not directly applicable to the employment-listrikan installation of low voltage \/ medium-large scale.<\/span> In this case the measuring device used is connected to the load but rather indirectly through measuring transformers consists of a current transformer and voltage transformer.<\/span> For the installation of low voltage electrification of large-scale typically only use current transformer, was for the installation of electricity medium voltage \/ high use current transformer and voltage transformer.<\/span><\/p>\n Measure transformer<\/strong><\/span> In accordance SPLN 76-87, current transformer (CT) should have primary current from 10 A, 12.5 A, 15 A, 20 A, 25 A, 30 A, 40 A, 50 A, 60 A, 75 A and multiples thereof , while the CT secondary current is 1A, 2 A and 5 A. (mostly 5 A).<\/span>
\n<\/strong> Measuring transformer is a transformer that is designed specifically for the purposes of electrical measurement.<\/span> There are two kinds of measuring transformers, which tarfo current (CT) and voltage transformer (PT).<\/span> Due to function only as a tool in the measurement of the measuring tarfo designed with low power, for example for special use current transformer 30 VA.<\/span><\/p>\n
\n In accordance SPLN 77-87, voltage transformer (PT) must have a secondary voltage of 100 V with a power of 10, 15, 25, 30, 50, 75, 100, 150, 200, 300, 400 and 500 VA.<\/span><\/p>\n