Electrician Notes

Safety Signs

• Warning signs: Indicate potential hazards.
• Mandatory signs: Prescribe actions that must be followed.
• Prohibition signs: Indicate actions that are not allowed.
• Information signs: Provide general information.

Fire Extinguishers

• Smothering: Isolating the fire from the supply of oxygen.
• Steps to use a fire extinguisher (PASS):
  • Pull the pin.
  • Aim at the base of the fire.
  • Squeeze the lever.
  • Sweep from side to side.
• Types of fire extinguishers used for electrical equipment fires: Halon type.
• Starving: Removing the fuel element from the fire.

5S Concept

• Step 4 refers to "Standardization".

Hand Tools

• Round nose pliers are used for making wire hooks and loops.
• Pincers: Used for extracting pin nails from wood.

Road Safety Signs

• Cautionary signs: Used for safety on roads.
• Warning signs: Have a yellow background.

Waste Disposal

• Incineration: A waste disposal method that produces heat.

Personal Protective Equipment (PPE)

• Nose mask: Used for protection from fumes.

Lifting Heavy Loads

• Cranes and slings, winch, layers and rollers, and machine moving platforms are used to lift and move heavy loads. $\textbf{PPE}$

Artificial Respiration

• Nelson’s arm-lift back pressure method is used for victims with injuries on the chest and belly.

Occupational Health Hazards

• Biological hazards can cause infection.

Diagnosing Cardiac Arrest

• Appears blue color around his lips.

First Aid

• Apply pressure over the injured portion to stop bleeding.
• If a victim is in contact with an electrical power supply, break the contact by switching OFF the power supply.
• If a victim injured on head with risk of dying the golden hour is the First 30 minutes.

COMA Stage

• Lie totally senseless and do not respond to calls.

Gauges

• The tool is used to check the internal radius of a job.

Files

• Rasp cut file.

Tools

• Inside caliper.

Timber Defects

• Twisting in timber is caused by uneven shrinkage.

Mortise Chisel

• Making rectangular holes in wood.

Sheet Metal

• Hatchet stake is used for sharp bends in sheet metal.

Cold Chisel

• Diamond point chisel is used for squaring materials at the corners.

Calipers

• Jenny caliper is used to draw parallel lines along the outer edges of materials.

Drill Bit

• Taper shank bit.

Sheet Metal Work

• Square stake is used for general purpose in sheet metal work.

ISO Metric Fine Thread

• In ISO metric fine thread M12 x 1.25, 1.25 indicates the pitch of the thread.

Timber

• Knot defect in timber is due to irregularity in the growth of the branches.

Files

• Triangular file is used for sharpening the blunt teeth of a tenon saw.

File Parts

• Heel.

Tool

• Jenny caliper.

Chisel Angle

• Point angle.

Firmer Chisel

• General chiseling work.

Half Lap Joint

• Middle-lap joint is used if one part of a job meets another part at some distance from the ends.

Notches

• V notch is used for making a metal tray with 90° bend and an inside flange.

Hem Folding

• Purpose of hem folding in sheet metal work is to prevent the sheet from damage.

Timber Defect

• Irregularity.

Hammer

• Claw hammer.

Timber Defect

• Cupping in timber is caused by improper seasoning.

Galvanized Sheet Pipe Joint

• Parallel female thread.

Notches

• Straight notch is used for bending the edge of the sheet.

Cross Cut Cold Chisel

• Cutting keyways.

Notch

• V notch is used to make a job with 90° bend.

Curve Cutting

• Key hole saw is used for internal cutting in wood.

Stake

• Blow-horn stake.

Tools

• Tack hammer.

Chisel

• Web chisel is used for separating metals after chain drilling.

Stake

• Blow horn stake is used for riveting or seaming tapered cone shaped articles.

Timbers

• Growth of branches cause knot defect in timbers.

Current Carrying Capacity

• The current carrying capacity of 32 amp. rated cable, if it is protected by the rewirable fuse is $26 Amp$.

Standard Wire Gauge (SWG)

• The possible range to measure the size of the wire in a Standard Wire Gauge (SWG) is $0-36$.

Wire Joint

• Knotted tap joint.

Soldering Flux

• Hydrochloric acid soldering flux is used for soldering galvanized iron.

Soldering Method

• Dip soldering is used for quantity production and for tinning work.

Under Ground (UG) Cable

• Bedding is the part marked as ‘X’ in the under ground (UG) cable.

XLPE’ Cable

• Cross Linked Poly Ethylene.

Underground Cable

• Serving layer in underground cable protects armouring from atmospheric condition.

Cable Laying Method

• Racks in air cable laying method is used in generating station.

Copper Atom

• There is 1 electron in the valence shell of a copper atom.

Neon Lamp

• Gas ionization effect is the effect of electric current on neon lamp.

Insulation Resistance

• Mega ohm is the unit of insulation resistance.

Electrical Device

• Rewirable fuses are the coarse excess current protection.

Wire Joint

• Western Union joint is used for extending the length of conductor in over head lines.

Soldering Flux

• Ker-al-lite is used for soldering aluminum conductors.

Molten Solder

• Tin content reduced due to repeated melting.

PVC Insulation

• Insulation resistance decreases when cable carries excess current continuously for long period.

Cable Laying

• Duct pipes is for congested areas.

UG Cables

• Lead sheath is the part marked as ‘X’ in UG cables.

U.G Cable

• Short circuit fault can be identified in the circuit.

Underground Cable

• Bedding protects the metallic sheath against corrosion.

Soldering Iron

• It prevents burns and fire if kept into a stand that not in use while soldering.

Wire Joint

• Rat tail joint.

Joint

• Married joint.

Britannia ‘T’ joint

• Tapping the service connection from overhead lines.

Soldering Method

• Soldering with a soldering iron is used for servicing and repairing work.

Dipsoldering Method

• Soldering miniature components on PCB.

Belted U.G Cable

• Lead sheath is the part marked ‘X’ in belted U.G cable.

Insulating Material

• Bituminous compound is used as hot pouring compound for making joints in under ground cable.

Bedding Insulation

• Protect the metallic sheath against corrosion in U.G. cable?

Test

• Loop test is conducted to locate the faults in U.G. cables.

Stranded Conductor

• Diameter of each conductor is represented by the number 1.40.

Aluminium Conductor

• $35 mho/m$ is the electrical conductivity of aluminium conductor.

Cable Rating Factor

• $0.81$ is the rating factor of cable provided with coarse excess current protection.

Neutral Conductor

• Half size of phase conductor in U.G cable

Tool

• Crimping tool

Joint

• Western union joint is the tool is used in over head lines for high tensile strength.

• The reading of micrometer is $4.55 mm$.

Conductors

• 16 Amp. Cable's current capacity is $13 A$.

Advantage of Stranded Conductor

• It is More flexible.

Unit for Quantity of Electricity

• It is Coulomb

Name of Soldering Method

• Soldering gun.

Electro Motive Force (EMF) Calculation

• $EMF = Potential \ difference + voltage \ drop$

Current Rating Factor Calculation

• Current rating factor for close excess current protection of cable is $0.81$.

Solid Conductor

• Solid conductor compare to stranded conductor has less flexibility.

Soldering Method

• Temperature controlled soldering is the name of the soldering method.

Soldering

• Insufficient heating is the cause for cold solder defect in soldering.

Electric Supply

• Bare conductors are used for distribution lines.

Conductors

• There are $18$ electrons in the third cell of the copper atom.

Semiconductor Material

• Germanium is a semiconductor material.

A.C. Supply Indicator

• Both electrodes will glow in neon polarity indicator used for checking A.C. supply.

Electrical Energy

• $2.5 unit$ consumed by 500W lamp for 5 hours.

Hot Resistance Calculation

• The hot resistance of a bulb rated as 100W/250V is $625.00 ohm$.

Electric Circuit Law

• Kirchhoff’s second law states that in closed electric circuit, the applied voltage is equal to the sum of the voltage drops.

Total Power Calculation

• Total power of the circuit the two lamps rated as 200W/240V are connected in series across 240V supply is $100 W$.

Parallel Circuit

• Parallel circuits have equivalent resistance $(RT)$
• Resistance Value Changes A conductor’s diameter doubles, the resistance value decreases to four times.

Series Circuit Indicators

• Indicate infinite resistance when reading ohmmeter across opened ‘R2 resistor.

Resistors

• Wire wound resistor is the name of the resistor.

Resistor Value

• The resistance value of the resistor by colour coding method is $23 x 10^{3} \Omega \pm 5\%$.

Ohm Meter Graduated Scale

• It is graduated with non- linear scale because the current is inversely proportional to resistance.

Wheatstone Bridge

• The unknown resistance ‘RDC’ in the Wheatstone bridge network is $9W$.

Temperature Coefficient

• Mica is having negative temperature co-efficient property.

Ohm’s Law Electrical Quantities

• Current, voltage and resistance.

Open Circuits

• In the parallel circuit with one branch opened, no current will flow in that branch.

Resistivity Unit

• $ohm - metre$ is the unit of resistivity.

Arc Quenching Protection

• Varistors resistor is used for Arc quenching protection in circuit breakers.

Colour Coding

• The resistance value by colour coding method is $22 x 10^{3} pm 10\%$.

Wheatstone Bridge Reading

• Value of the meter “V” is $18V$.

Series Circuit

• Multiplier resistor of a voltmeter is the application of series circuit.

Opened Resistor in Series Circuit

• Total supply voltage will appear across the opened resistor in series circuit.

Shorted Points

• Circuit resistance is zero if ‘ab’ points are shorted.

Resistance Name

• If the temperature increases, resistance increase and that resistor is called Sensistors.

• Quantity of Electricity (Q) can be dertermined with: Current x Time

  Conductance Unit:

• Mho is unit of conductance

Temperature Effect

• Temperature co- efficient defines the change in resistance in Ohm(Ω) per degree centigrade (°C).

Voltmeter

• Moving coil voltmeter is used to test the polarity of battery.

Resistor

• The voltage drop across the resistor ‘R2’ in the series circuit is $10 Volt$.

Series Circuit

• Fuse in circuit is an application of series circuit.

Measuring Method Resistance Range

• Wheat stone bridge method is used for measuring $1 \Omega to 100K \Omega$.

SI Unit of Specific Resistance

• $Ohm-metre$ is the SI unit of specific resistance.

Resistors

• The value of the resistor is $3300 \pm 10\%$.

Shunt Resistance

• Shunt resistor R2: To adjust the zero position of the pointer.

Heat Generation

• Electrical quantity: Square of the current

Resistance

• If the cross section the area is doubled resistance decreases 2 times.

Voltage Drop across Resistor

• Voltage drop across the resistor ‘R4’ in the circuit is $100 V$.

Resistor

• If the light intensity increases then Light Dependent Resistor (LDR) decreases.

• Formula for Power

• Voltage × Current

• Calculation of Heat Resistance rated lamp: 312.5

• Value of Resistance calculation in open circuit is infinity

• Lowest Current flows Resistance in parallel Value is 560

• The Specific Resistance Value of Copper Conductor is The specific resistance 1. 72 Micro ohm/cm3

• Inversely Proportional resistance is Area of Cross Section

  Total Capacitance Calculation:

• In the circuit is 6uF

• The Unit of the Capacitance is Farad

• Calculation of Capacitance Value formula = .014

• How one can decrease the Capacitance ValueIncreasing the distance between the plates

• The is Diamagnetic Substance is Water one the following options

• Factor which will affect the Polarity of the ElectroMagnet is Direction of Current

• The formula for Magneto Motive Force (MMF) Ampere-turns

• Three Inductors are connected with Series with the formula LT = L1 + L2 + L3

• Permeance calculation is Weber/Ampere turns

• Cork Screw rule is applied to find the direction of the Magnetic fields in a Solenoid Coil?

Series Circuit

• The total Series circuit Capacitance calculation =15ufd

Voltage Differences Capicators

• Each Voltage drop is less than Voltage reading
  Paramagnetic Substance

• the Para Magnetic Substance isCopper from one the following parameters given
  B.H curve parts

• coercivity is part marked in B. H curve
  Conductance

• The similar for conductivity is permeance for Electric current
  Retentiveness
  *Ampere turn / Weber - Retentiveness Unit
  Correct Expression of Capacitance

• Equation For capacitance C= Q/W - Q’ and the voltage being ‘V’
  Electromagnet’s Pulling Strength: Increase the field strength Increase the field intensity
  Magnetizing Force:

• defines The flux density is always lagging behind of the magnetizing force Hysteresis
  Effect of Surrounding Metal:

• Effect is eddy Current in the Magnetic field.
  Capacitors for Air Application:

• TV Turners in are generally used the capacitance
  .Capacitance Polarized Electrolytic :
  *Will Explode one polarity changes
  Magnet Materials
  *Wood Material is in Magnetism
  S.I Unit of Lux Density

• Tesla is S.I Unit. Of Lux Density

• Shape factor that is related to B-H Curve factor Magnetic Related

• eddy current Is Frequent in B. H curves.
  Changing Permeability

• When the Flux density increases
  Type of Capacitor using Space Electronics

• Electrolyte Tantalum

• It’s will Not Function during the defect called Open Circuit

• Changes in value of Decreasing distance in Plates Increases is one them in Capacitor

• One Property in is Magnet is Directive Property

• A parametric Substance in Air.
  What method is used to make commercial purposes with Permanent Mags.

• Commercial Mag Induction purpose.

• In turns value when the space in Increases in Decays .Effect of Inducatance in Decays

• Dielectric Insulator is Used capacitor is Plates Protect From short -circuit

• Area of plate is factor of determine capacitive value
  Capaitors RF

• Coupling Circuits: - used monolithic

• Susceptance SI is Mho
  *Resistance formula : 42. 5

• Increasing capacitance: Reducing capacitance
  Formula to find Three Phase Reactive Power (PR): *SinTHETA

• Below0.5 lagging is inductive Load power factor

• Current Three Star load. algebraic sum of currents

• Reactive Power Calculation :11.5 KVA apparent power

• zero power factor : Opposite signal WattMeter.
  *240v voltage :339.5v value of peak voltage.
  *Resinance Formula *Inductive 0.1
  Reactance 0.1 = Value equal
  Reactive Powe Formula- * formula- = VI 0.5 8
  Impendence is 12:5 , X 41=36,X,1= 24 formula value is ohm
  Single PH AC circuit: Phase displacements: =90 11 = = Star relationship voltages- : 20 volts = Phase sequence Meter function is to Phase sequence Meter function is to Ensure the correct phase
  415v ,0- power 7884
  Two wattmeters =2 show total power - 2=0.5
  Calculate The power factor of coil: 5A, =0.5
  Calculate Impedance if L.C series circuits= 0 -240 01 -8 sin

• The power of A.c RC circuit = Power factor = = 0 A / 20

• To make the low power by improving AC circuit formula is capacitor paralleled

• the Power formula If sine A Theta Power = sin Theta The power formula If sine A Theta Power = sin Theta

• The = power relation in L.c circuit = = formula is = is L = .3 4 L= -3
  Measure the 3 AC Artificial The measure three 3AC Artificial Star
  R factor=formula is Maximum =form average 2A +
  *RL2= Z = ohm
  *Negative reading in watts meters The- correct option: 54 (c) by reversing by replacing