electrialstandards

Resistance is only component availbale which converts current into voltage and voltage into current. Resistance in Series:- In Series resistance are additive and are as described below:- If there are resistances are R1, R2, R3, R4 ----- RN are connected in Series then equivalent resistance is given as  R (Eq.)= R1 + R2+ R3+ R4+ ---------------------+RN Series resistance is known as voltage divider circuit in which voltage get divided but current remains the same. Whenever resistance is added in series then equivalent resistance is getting increased. To know about capacitors in Series and Parallel Visit:- http://electrialstandards.blogspot.in/2015/05/capacitor-in-series-and-parallel.html Resistance in Parallel:- If there are resistances are connected in Parallel then equivalent resistance is given as :- If there are resistances are R1, R2, R3, R4 ----- RN are connected in Series then equivalent resistance is given as          1       =    1    +   1    +     1     +    1    +  -----

Lighting emitting diodes mostly known as LEDs are now becoming integrated part of every Industry, Household , Shops and everywhere as they offer plenty of advantages some of them main are such as power saving and long life. There is curiosity arises how these LED’s will work? Working principle of the same is as below:- LED is capable of emitting a fairly narrow bandwidth of visible or invisible lights and LED emits lights usually of orange, red, yellow, or green colors. The invisible light that LED emits includes the infrared light. LED consists of a P-N junction diode. When electric current is applied to that P-N junction then that junction emits light .This sensation is generally called Electro-luminance in electronics. Electro-Luminance is defined as the emission of light from a semi-conductor under the influence of an electric field. At PN junction there are electrons at N- Region and Holes in P- region. These combine at PN Junction. Free electrons at N- Region are in the conduct

There is quite confusing question most of the time asked in interview is that if there are three bulbs having ratings as 60W, 30W and 20W and these bulbs are connected in parallel then which of these bulb will be brightest?? Answer to that question is that in Parallel   1               =  1  + 1  +   1 R(eq)             R1   R2    R3 Multiply both sides by Rated voltage square i.e. (V Rated ) 2 We get (V Rated ) 2    = (V Rated ) 2 + (V Rated ) 2   + (V Rated ) 2 R(eq)              R1                R2               R3 This means P(eq)= (P1)+(P2)+(P3) This means in Parallel Power will be additive In series we get R(eq)= R1 + R2 + R3 Now divide both sides by (V Rated ) 2 We get R(eq)      = R1 + R2 + R3 (V Rated ) 2            (V Rated ) 2 Thus we get    1         =     1      +      1     +     1 P(eq)          P1           P2        P3 Thus we see that when all bulbs are connected in Parallel then 60W i.e. highest rating will be brightest and when all bulbs are connected

LED VS CFL VS Incandescent Light Light Emitting diode is having Life span of 5000 Hrs , Incandescent light is having life span of 1200 Hrs and CFL has life span of 8000 Hrs. LEDs use less power per unit of light generated (lumens).     LEDs help reduce electric bills LED’s consumes 6-8 watts against 60W in incandescent light and 12-15 watts in CFL for same lumens. This will leads to huge power saving in a year against other available incandescent and CFL’s. Although LED’s having initial cost against incandescent and CFL’s but payback period is from 6-8 months only depending upon usage and electricity charges in different geographies. For knowing how LED works please visit the link below:- http://electrialstandards.blogspot.in/2014/12/light-emitting-diode-working-principle.html Also there are environmental effects also LED doesn’t use toxic mercury but incandescent and CFL’s contains mercury. Lower energy consumption decreases: CO2 emissions, sulfur oxide, and high-level nuclear wast

Generator connected to Isolated load:- When the prime mover I/p is increased while the excitation remains constant; it results in an increase in frequency. The increase in frequency increases the terminal voltage for the same excitation. The increase in  terminal voltage causes the static load to increase their respective demands as their power consumption is proportional to square of the voltage. The rotating load have their respective speed increases because of the increase in frequency that increases their synchronous speed. The increase in voltage results to increase in their developed torque and consequently the power demand may increase particularly when they are driving constant torque load. The twin factors results in as increased power demand by the rotating power load as well. The final conclusion is that an increase in prime mover I/P alone results in increase in frequency as well as increase in Unit loading. If the excitation increases while the prime over I/P remains cons