tamilkamathaigal

We often observe day to electrical faults in our appliances such as  1.Tube rod get faulty  2. Lights not working  these are all happens due to Aging of equipment's Below are the faults which are not in control:- 1. High voltage from source 2. Low voltage from source these types of abnormalities usually effect electronic equipment's such as TV, fridge, Microwave etc.  So to avoid faults in these equipment's usually Stabilizers are installed for them. So that any abnormality in source voltage could not effect our load end.  But severe fault occurred when neutral get breaker from transformer in that case in that case Neutral becomes a floating neutral and phase starts coming in Neutral. Which causes burning of every equipment and even may cause fire if lights not switched off in line.  Now Question arises How voltage starts coming in Neutral? Answer for the same is that During neutral break if Transformer load is balanced then lights and equipment doesn't bur...

Choke is very important of Tube light. Usually tube light doesn't work without choke. Working:  Normal operating voltage of tube light is about 110 but naturally available voltage is 240 V in India hence the choke comes into picture which gives 110 V output. But for initiating the light (to ionize the gas in the tube) the system, system requires 800 - 1000 V to provide this starter has been used, which block the current flowing from the choke to light hence the voltage will build up across the load. once the maximum voltage reached which starter can withstand, the starter closes the circuit and the build up voltage applied across tube light. Principle:- Choke is actually an Inductor As we know inductor opposes the rate of change of current here we are making current I which is intially drawn to zero with the help of bimetallic contacts present in starter According to formulae E=L*di/dt here L is constant and di is equal to I-0 and dt is time taken for I to become zero Ac...

This is the color of the light as perceived by the human eye. It is measured in degrees Kelvin (°K) • The general terms used for artificial light colors are: Warm White -- 3000 K Cool White   -- 4100 K Daylight       -- 6500 K – This is what our bulbs & tubes are Detailed application of Different color temperature:- 5000- 8000 K -- Daylight White for Petrol Pumps & Winter good shops 4000-5000 K  -- Cool White for Offices, Hospital, industries 3500-4000 K  -- Super Stores, Showrooms 2700-3000 K -- Warm White For Residential Lights, Restaurants 2000-2500 K -- Extra Warm for Display, Street lights

Lets continue with Fundamentals of Electrical Engineering:- 1. Whenever checking electricity supply in Industry then keep assured with Multimeter as sometimes line tester may get failed and will not function and also Line tester even starts glowing at 5 V only. 2. Megger should be used to check motor winding resistance, Insulation of motor Multimeter may not always gives correct data. 3. In an Industry grid should be formed for Earth pits. As in grid all earth pits resistance comes in parallel with each other which will ultimately resistance of grid. Whenever earth fault occurred then fault current will go through grid as Grid offers lesser resistance. 4. Separate grids should be formed for Electrical and Electronic pits. 5. Double earthing of electrical system is required where there was there phase system is used and single earthing is sufficient in case of single phase system. 6. Electricity is not flow of electrons it's the vibration of electrons. 7. 3-Phase Motor direction can...

Below are the Most important fundamentals of Electrical Engineering:- 1. Electricity always from Source to load and never ever comes back from load to Source. 2. For current flow there must be Potential difference and current always flows from High potential to low potential. 3. In single phase system whatever current a load draws will return back through Neutral. 4. Capacitor bank current is not active current but it is reactive current so don't confuse. 5. Fault current always flows backwards i.e. if fault occurred at Motor then first it's O/L get tripped not directly causing Transformer tripping. Although current is drawn from Source but fault current always from Fault end to backward as during fault load which draws current that load resistance reduced to very low value due to which high current flows during fault. That is how Electrical system is designed for load fault current. 6. When motor is connected in Delta who has six leads then 2 Electrical supply phases are conne...

Methods of Earthing:  Below are the various method of earthing:- 1.Plate Earthing 2.Pipe Earthing 3.Rod Earthing Plate Earthing:- In this type of earthing plate either of copper or of G.I. is buried into the ground at a depth of 3 Meter or greater than 3 Meters, Earthing plate should not be buried lesser than 3 Meters. Earthing plate is filled with layers of salt and coke not less than 1.5 feet so to provide provide lesser resistance.The earth is securely bolted to an earth plate with the help of bolt nut and washer made of copper, in case of copper plate earthing and of G.I. in case of G.I. plate earthing. For GI earthing Plate Size should be -- 600 mm X 600 mm X 8.30 mm For Copper earthing Plate Size should be-- 600 mm X 600 mm X 3.15 mm Pit Size made for maintenance should be 1 Feet X 1feet so as to provide ease of accessibility of maintenance of these earthing pits and for testing of earthing pits. Below is pictorial view for how to construct earthing pits using Plate earthing...

Earthing is required for protection of both man and machine. In day to day activities we are using electrical and electronic appliances e.g. for Fans, Television, Lights etc. For protection of both man and machine earthing is used. Earthing provides protection against fault in the system. These faults are associated with very heavy currents which may leads to shock to persons working on the system and even causes failure of equipments. There is underlying principle in electrical systems that "Current always follows low resistance path. H uman body is having high resistance but whenever there is fault in system then that current starts flowing th so if earthing is provided then current will flow in to earth and protect human beings from Shock. Picture shows below how earthing can protect a Human being from Shock. Earthing means connecting the neutral point of supply system or Non current part such as body to the earth via low resistance path. Good Electrical Earthing & Its...

Capacitor banks are used for compensating reactive load connected at load end. It is usual practice to keep KWH consumption = KVA consumption KWH consumption= Voltage X Current X power factorX time KVAH consumption= Voltage X current X time Now Power factor= KWH/ KVAH Now if power factor is low then there will be higher KVAH consumption as KWH is constant. So lower power factor leads to higher current as voltage of system is constant. This will leads to higher KVAH than KWH and leads to higher billing in case of lower factor. Capacitor banks are most widely in industries to save electricity bill as in industries billing is done in KVAh.  KVAH can become equal to KWAH when unity P.F. Is achieved as most industrial motors and lighting load having p.f. ranging from 0.7- 0.8 which causes KVAH to be very high in comparison to KWh. This lower factor is due to reactive component of power in order to compensate this reactive component of power capacitor bank is used in parallel with load....

Capacitor banks are used for improving PF of the system. It was very interesting to find out that all capacitor banks  are connected in Delta instead of star. There are many advantages of connecting capacitor bank in Delta instead of Star connections , Same will be discussed as below:- 1. Lower Maintenance cost In a delta connected capacitor if any cell out of three get faulty then KVAR of capacitor bank get dropped by 27% means capacitor will work in open delta connections. Now that faulty cell will be replaced very easily by just opening the leads. This way maintenance cost will be reduced considerably as cost of replacement of one cell is needed to be bear instead of whole capacitor. For MCCB standards:- http://electrialstandards.blogspot.in/2013/10/mccb-standards.html 2. Higher Efficiency In Delta circuit Current is high in comparison to Star connections.  Which will leads to higher  high efficiency in case of Delta connections. 3. Higher capacitance If you solve for ...

MCCB name is derived from Moulded case Circuit breaker Breaker. MCCB is used for following purposes :- (i) ON/off of electrical load connected across MCCB (ii) Protection of  an electrical circuit from damage caused by overload ,short circuit and earth fault. Difference between MCCB and Isolator:- This means MCCB also provides protection against overload, Short circuit and earth fault which an Isolator can't do. Isolators are only used to isolate the power supply to circuit. It is used to interrupt the circuit as soon as any fault occurred and they are used in every industry where connected load is having current rating above 100A . Difference between MCCB and Fuses:- MCCB are completely different from fuses. Fuses are used only for interruption  of the circuit and get blown off after it's operation. Although they serve the same purpose in case of any fault in system as these isolate the circuit after getting blown off. But in MCCB , MCCB get tripped in event of fault and sam...