Tricky but Easy Electrical Engineering!
If you go through the catalog of any instrument having digital display, you may notice that its display is given like three and half (3½) or four and half (4½) LCD display. So what does this mean or what information does this provide? Basically, there are two types of digits in digital display: Full digit … Read more
What is Busbar Protection? Busbar protection is a protection scheme meant to protect the busbar from electrical fault. Various feeders are connected to a busbar through circuit breaker in any of the bus configuration viz. Double Busbar arrangement or one and half breaker scheme. The main purpose of this busbar is to increase the reliability … Read more
Phase Sequence Indicator is an instrument which identifies the phase sequence of three phase supply system. Phase sequence or often called phase rotation of 3 phase supply system is defined as the sequence or order in which voltage in R, Y and B phase is attains their maximum value. Normally the phase sequence is RYB. … Read more
Parallel operation of three phase transformer is very common in three phase power generation, transmission and distribution. It is advantageous to use two or more Transformer units in parallel instead of using a single large unit. This offers flexibility for maintenance as well as operation. Advantage of Parallel Operation of Three Phase Transformers It increases … Read more
Megger is a brand name of Insulation Tester. Due to the popularity of this brand, we often use this term to mean Insulation Tester and Megger value to mean Insulation Resistance value. Today, there are various other make of Insulation Testers available and therefore it is better to call it Insulation Tester instead of Megger. … Read more
The rating of transformer is given in terms of its kVA, HV/LV voltage and phase rotation (for three phase transformer). To calculate the rating of the transformer for both single phase and three phase, the load required to be fed and voltage at which load is to be fed must be known or should be … Read more
Rotating magnetic field is magnetic field which rotates in space about some point or axis. The North and South poles continuously rotates with a specific speed, called synchronous speed. All poly phase electrical machines are associated with rotating magnetic field in the air gap. Therefore, an understanding of rotating magnetic field produced by poly phase … Read more
Induction Motor works on the principle of electromagnetic induction. The three phase input power supplied to stator terminal is converted into mechanical power at the shaft output. This conversion of energy takes place through magnetic coupling between stator produced rotating magnetic flux and rotor bars. The power transfer from stator to rotor takes place through … Read more
Air gap in rotating electrical machine is a coupling medium to transfer electrical energy from stator to the rotor or vice versa. It is also required for free rotation and proper cooling of the machine. Generally air gap length is kept as low as possible due to several reasons. But if we compare the air … Read more
Sign convention is the generalized way to solve and analyze the electrical circuits. It defines the positive or negative sign to be taken for various electrical parameters viz. current, voltage, power etc. Sign convention brings uniformity in the value of electrical parameters so that anyone can understand the analysis of circuits. Our Universe is diverse … Read more