The installations wherein CTs and VTs are mounted to measure the normal and abnormal values of current and voltage, have many variations in key system parameters, including voltage class, insulation… Read more
Feb 18, 2019 | Edvard
A three-phase service can be supplied by one three-phase transformer unit or by interconnecting three single-phase transformer units. One three-phase unit is smaller than an equivalent size bank consisting of…...
Feb 08, 2019 | Edvard
A transformer-feeder include a transformer directly connected to a transmission line circuit without the intermediation of a HV switchgear. The saving in HV switchgear so achieved is unfortunately lowered by… Read more
Jan 28, 2019 | Edvard
In order to calculate short-circuit currents, it is obligatory to know conductor-specific equivalent data and impedances of electrical operational equipment, which are usually given by the respective manufacturer. The calculation…...
Jan 25, 2019 | Edvard
There are many terms related to the power transformer operation that can be easily visualized which are especially important for students, like for example transformer construction or regular working principle…. Read more
Jan 21, 2019 | Edvard
The utility supply voltage depends on both availability and consumer requirements. The consumer transformer is connected delta on the high-voltage side and grounded wye on the low-voltage side. A fused-disconnect… Read more
Jan 07, 2019 | Edvard
Once oil filling is completed, various pre‐commissioning checks and tests are performed to ensure the healthiness of the transformer (or reactor) prior to its energization. Various electrical tests must be… Read more
Dec 26, 2018 | Edvard
If the voltage or current in a power circuit are too high to connect measuring instruments or relays directly, coupling is made through transformers. Such measuring transformers are required to… Read more
Dec 03, 2018 | Edvard
The installation of a dedicated substation to serve a plant actually involves an interface between the utility and the plant. Close coordination between utility and plant personnel is essential so… Read more
Nov 21, 2018 | Edvard
Polarity is very important for the operation of transformers and protection equipment. A clear understanding of polarity is useful in understanding and analyzing of transformer connections and operation as well… Read more
Nov 19, 2018 | Edvard
