Showing posts from October, 2018

Celling Fan Wiring Diagram with Capacitor Connection

How Wiring a Celling Fan with Capacitor Connection?In the above schematic wiring diagram of a celling fan shows the very simple and easy external connection that connection of celling fan, fan speed regulator, ON/OFF switch with single phase power supply at home.
Also, shown the internal connection of running coil/winding, starting coil/winding and capacitor.

Why Capacitor is Required in a Celling Fan Connection?A motor need two windings, main winding to run the motor and astarting winding to start the motor. 
Ceiling fan is a single phase induction motor, which doesn't have the property of self starting. For a single phase AC motor 2 separate phases are required to produce a rotating MMF(Magnetomotive Force) which in turn rotates the rotor. 
But, common household electricity supply consists of only one phase. So, we must introduce a circuit which produces the second phase. 
Ceiling fan contains two winding, a starting winding and a running winding. capacitor is connected in series wit…

How Does A Simple Lightning Conductor Protect A Building?

How Does A Simple Lightning Conductor Protect A Building?

Lightning conductor or Lightning rod is a metal rod or wire that fixed to an uncovered part of a building roof or other tall structure to collect lightning destruction and divert harmlessly into the ground.

Lightning conductor or Lightning rod is the same thing, in UK people say Lightning conductor on the other hand US & AUS people call it Lightning rod.

So, the name lightning conductors recommends that it conducts the electric charge which come from cloud and hits on the building.

This simple equipment attract like magnetic action to lightning charges, harvest them and send to the ground through the wire connected with roof top lightning rod and buried metal plate at bottom.

Do you interested to know more detail about  Difference Between Lightning and Surge Arrester
also may like  Specification of high voltage Surge Arrester.

How Does Lightning Work?Lightning rod or lightning conductor does not allow the electric charg…


What is CT or Current Transformer in Electrical Distribution System
The CT in abbreviation of Current Transformer is a type of instrument transformer that used to measure the current in AC or Alternating Current systems, taking the reduced amount from it’s secondary winding which is proportional of primary winding that being to measured.

In the low voltage system where current flow limit within 100A, is possible to measure directly or whole current metering system. For low voltage system current more than 100A and all high voltage system, current measured by using CT. Actually CT takes a reduced portion of current which is proportional to flowing total current in the load circuit.

The instrumental transformer CT is required for low voltage high amount or high voltage system current measuring because of conventional measuring instrument is not practical to design to measure in high voltage or high current directly.

So, Current Transformer’s working principle is not different from ordinary…


How Calculate Capacitance of Underground Power Cable?Capacitor is nothing but a two parallel metal plate separated by a dielectric that store electrical energy; formally we can define capacitor is a passive two terminal electrical component that used to store energy electrostatically in electric field, it also known as condenser. Practically a capacitor usually used a thin films of metal, aluminum foil or disks, etc.

The property of capacitor is known as capacitance, means the capacitance is the ability of a body to store an electric charge. The unit of capacitance is farad, symbol of farad is F, mostly common is micro farad µF.
The formula to calculate the capacitance between two cables is as C = (Permittivity*Area)/D,
Where, A is the area is that of one cable, D is the distance between the center of the cable and the permitivity is that of the material between the cables.
Capacitance may measure as C= Q/V= Charge/Potential difference.

How Calculate Single Core CableLet,r = radius of the i…

Transformer Winding Resistance Test by DC Current

How Do You Do Transformer Winding Resistance Test by DC Current?Considering the basic principle of operation is to inject a DC current through the transformer winding to be measured, and then read the voltage drop across that winding. 
We may refer to formula for DC voltage across the transformer  is, V = I * R   where,  V= DC voltage across transformer winding; I = DC current through transformer winding; & R = desired calculated resistance of the transformer winding.
How Prepare for Transformer Winding Testing?Selecting the Proper Current Range, transformer manufacturers typically recommend that the current output selected should not exceed about 10% of the rated winding current;Cause erroneous readings due to heating of the winding; Always choose the highest current output possible for the expected resistance value; Typical ranges are 0.1-10 % of rated winding current;The temperature of the winding shall be assumed to be the same as the temperature of the insulating liquid;It should n…


The Inspection and Testing Procedure to Ensure Quality
The underground power cable transmission line, whole Plant supplied and works constructed under the contract should be subject to inspection and testing by the Engineer, by the Employer or, where appropriate by an approved inspection authority should they so require, during manufacture the equipment, erection the plant and after completion the installation works.
The inspection and testing should include but not be limited by the requirements of this article of the specification and of the detailed inspection. Prior to inspection and testing the plant and equipment should undergo pre-service cleaning and protection as specified in the section of the specification. Following Inspection and Test should be carryout in the underground power cable transmission line project: ·FAT or Factory Acceptance Test, before shipment the plant or equipment this test must be completed; ·PLI or Post Landing Inspection, after arrived the plant or equipme…