1year lab manual_eee

8/13/2019 1year Lab Manual_eee

1/26

MEASURMENT OF VOLTAGE, CURRENT, POWER AND POWER

FACTOR USING RLC LOAD

Expt No: Date:

AIM:

To measure power in a single phase AC circuit using wattmeter by RLC loading.

APPARTUS REQUIRED:

SL.No Name of the Apparatus Range / Type Quantity

1 Voltmeter (0-300V) MI 1 No.

2 Ammeter (0-10A) MI 1 No.

3 Wattmeter 300V,10A,LPF 1 No.

4 RLC Load 5kW 1 No.

5 Connecting Wires 1/18 SWGAs per

requirement

THEORY:

Power in an electric circuit can be measured using a wattmeter. A wattmeter consists of

two coils, namely current coil and pressure coil or potential coil. The current coil is marked as

ML and pressure coil is marked as CV. The current coil measure the quantity that is proportional

to the current in the circuit the pressure coil measures quantity that is proportional to the voltage

in the circuit. The given wattmeter is loaded by direct loading. The ammeter is connected in

series to the wattmeter. Since the same current flows in both the coils, the current and voltage

across the circuit are constant. The power consumed by the load is measured using the wattmeter

and calculated using the relation given below.


2/26


3/26

FORMULAE:

Actual power = W x Multiplication factor(Watts)

Where, W Observed watt meter reading(Watts)

Apparent power = VI (watts)

Where, V Voltmeter reading(V)

I Ammeter reading(A)

Power Factor, cos = Actual Power / Apparent Power

PROCEDURE:

1. Connect the circuit as shown in the circuit diagram.2. Initially no load is applied.3. Autotransformer is set to minimum voltage position before switching on the power supply.4. Set the rated voltage by using the autotransformer. Measure and record the values of voltmeter,

ammeter and wattmeter on no load condition. Also carefully note the multiplication factor of

the wattmeter that is mentioned in the wattmeter itself.

5. Apply the load by adjusting RLC load.6. Measure and record the values of voltmeter, ammeter and wattmeter.7. Repeat the steps 5 and 6 until the ammeter reading reaches 10A.8. After taking all the readings, reduce the load slowly to the minimum and bring the voltage to

minimum in the autotransformer. Switch off the power supply.

9. Calculated the Indicated power by the given formula.10.Calculate the power factor by the given formula.

RESULT

A singlephase wattmeter is used to measure powe r in AC circuit using RLC loading.


4/26


5/26

OBSERVATION TABLE:

Multiplication Factor =

Voltage CurrentWattmeter Reading

Actual Power Power FactorSl.No (watts)

V (V) I (A) (watts) cosObserved Actual

MODEL CALCULATION:


6/26

HOUSE WIRING

Expt.No: Date:

AIM:

To Construct House wiring using Energy Meter

METERIALS REQUIRED:

Sl.No Name of the apparatus Range / Type Quantity

1 Switch SPST, 5A 3 Nos.

2 Incandescent Lamp 100W 1 No.

3 Lamp Holder Batten 1No.

4 Ceiling rose - 1No.

5 Socket 10A 1No.

6 Screws 1inch As per required

7 Wires 1/18SWG As per required

8 Switch Board 12x 8 1No.

9 Energy Meter1 300V , 16A

1No.750 rev 50Hz

10 Main switch Box 1 300V , 16A 1No.


7/26

TOOLS REQUIRED:

Sl.No Name of the tools Quantity

1 Combination Pliers 1 No.

2 Connector screw driver 1 No.

3Screw driver 1 No.

4Electrician knife 1 No.

THEORY:

Conductors, switches and other accessories should be of proper capable of carrying

the maximum current which will flow through them. The following table shows the rating for

different accessories. Conductors should be of copper or aluminum. In power circuit, wiring

should be designed for the load which it is supposed to carry. Power sub circuits should be kept

separate from lighting and fan subcircuits. Wiring should be d one on the distribution system

with main and branch distribution boards at convenient centers. Wiring should neat, with good

appearance. Wires should pass through a pipe or box, and should not twist or cross. The

conductor is carried in a rigid steel conduit conforming to standards or in a porcelain tube.


8/26


9/26


10/26


11/26

STAIRCASE WIRING

Expt.No: Date:

AIM:

To control the status of the given lamp by using twoway switches

METERIALS REQUIRED:

Sl.No Name of the apparatus Range / Type Quantity

1 Incandescent Lamp 100W 1 No

2 Lamp Holder Pendent Type 1 No

3 SPDT Switch 230V,5A 1 No

4 Wires 1/18As per

requirement

5 P.V.C Pipe 1/4"As per

requirement

6 Wooden Board - 1 No

7 Round block - 1 No

TOOLS REQUIRED:


1 Combination Plier 1 No

2 Connector screw drivers 1 No

3 Screw driver 1 No

4 Electrician knife 1 No


12/26

SWITCH POSITION VERIFICATION TABLE (TWO WAY SWITCHES)

Sl.No POSITION OFSWITCH 1 POSITION OFSWITCH 2 LAMP STATUS

1 1, 2 2 , 1 ON

2 1 , 2 1 , 2 OFF

3

4


13/26


14/26

PROCEDURE:

1. Place the accessories on the wiring board as per the circuit diagram.2. Place the P.V.C pipe and insert two wires into the P.V.C pipe.3. Take one wire connect one end to the phase side and other end to the middle point

of SPDT switch 1

4. Upper point of SPDT switch 1 is connected to the lower point of SPDT switch2.5. Lower point of SPDT 1 is connected to the upper point SPDT switch2.6. Another wire taken through a P.V.C pipe and middle point of SPDT switch 2

is connected to one end of the lamp holder.

7. Another end of lamp holder is connected to neutral line.8.

Screw the accessories on the board and switch on the supply.

9. Circuit is tested for all possible combination of switch position.

RESULT:

The staircase wiring is completed and tested


15/26

CIRCUIT DIAGRAM:


16/26


17/26

FLUORESCENT LAMP WIRING

Expt.No: Date:

AIM:

To make and check the fluorescent lamp wiring

METERIALS REQUIRED:

S.No Name of the apparatus Range / Type Quantity

1fluorescent lamp fixture 4 ft

1 No

2 fluorescent lamp 40W 1 No

3 Choke 40W, 230V, 1 No

4 Starter 1 No

5 Wires 1/18As per

requirement

TOOLS REQUIRED:


1 Combination Plier 1 No

2 Connector screw drivers 1 No

3 Screw driver 1 No

4 Electrician knife 1 No


18/26

THEORY:

Tube light has filament on either side. They are coated with tungsten material. The inside of

the tube has phosphorous coating which is used to convert ultraviolet into visible light and to give

the required color sensation. A choke is used to give transient high voltage so as to initiate theelectron movement which is an iron starter capacitor is used to suppress radio-interference with the

switch closed. The current flows through the choke and the starter. The glow switch suddenly

breaks thereby creating the circuit. Due to high conductivity, inductive property of the choke, a

transient high voltage is available across the filament. Hence the electrons are emitted and travel

through the tube. Then tube light is produced.

PROCEDURE:

1. Give the connections as per the circuit diagram as shown in figure.2. Fix the tube holder and the choke in the tube.3. The phase wire is connected to the choke and neutral directly to the tube4. Connect the starter in series with the tube.

RESULT:

Thus the connection of fluorescent lamp wiring is made.


19/26

MEASURMENT OF ENERGY USING ENERGY METER

Expt No: Date:

AIM:

To measure the energy in a single in a phase phase circuit using directloading

APPARTUS REQUIRED:

SL.No Name of the Apparatus Range / Type Quantity

1 Single phase Energy meter 750 rev / kWh, 240V, 1No.50Hz

2 Wattmeter 300V, 10A, UPF 1No.

3 Voltmeter 300V, MI 1No.

4 Ammeter 10A, MI 1No.

5 Load Resistive, 5kW 1No.

6 Wires 1 / 18 SWG

As per

Requirement

THEORY:

The energy meter is an integrated type of instrument, where speed of rotation of

the aluminum to the power consumed and number of revolutions per minute is

proportional to the energy consumed by the load.

The ratings associated with the energy meter are.

Voltage

rating

Current

rating

Frequency

rating Meter

Constant


20/26


21/26

The driving system of the meter provides the rotational surface of the torque for the moving

system, which in turn activates the energy meter. The energy meter is operated at induction

principle in which eddy current.

Indicated in the aluminum disc interacts with the main field and creates the driving force.

FORMULAE:

Energy meter specification = 750 rev / kWh

True energy = Power (P) x time (s)

= P x t (ws)

= P x t / 3600 x 1000 kWh

Measured energy = n / 750 kWh

Where n - number of revolutions / sec

`

PROCEDURE:

1. Connections are made as per the circuit diagram.2. Supply is given to the switch by closing the DFST switch.3. By adjusting the voltage is brought to the rated voltage.4. Load is switched On5. Time taken for five revolutions in the energy meter is noted and the corresponding

ammeter and voltmeter reading are noted.

6. The above procedure is repeated for different load current and for fixed number ofrevolutions.

7. Then the load is gradually released and supply is switched OFF.

RESULT:

Thus the energy in a single phase was measured using energy meter.


22/26

OBSERVATION TABLE:

M.F ----------------

SupplyLoad Current

WattmeterTime

True Energy Measured

Sl. No Voltage Reading p x t energyI (A) t (sec)

V P (W) 1000 x 3600 n / 750 (kWh)

(kWh)

MODEL CALCULATIONS:


23/26


24/26

MEASUREMENT OF EARTH RESISTANCE USING

ELECTRICAL EQUIPMENT

Expt No: Date:

AIM:

To measure the resistance to earth / insulation resistance of the order of mega ohms.

THEORY:

For this experiment we have to use the Megger. Is is an instrument for testing the

Insulation resistance of the order of mega ohms.

PRINCIPLE:

A megger consists of an emf source and a voltmeter. The voltmeter scale is calibrated in ohms.

In measurement, the emf of the self-contained source should be equal

that of the source used in calibration. The deflection of the moving system depends on the ratio of the

currents in the coils and is independent of the applied voltage. The value of unknown resistance can be

found directly from the scale of the instrument. Figure shows detailed diagram of a megger. It consists

of a hand driven dc generator a emf about 500v.the permanent dc meter has two moving coils. First oneis deflecting coil and another another one is controlling coil. The

Deflecting coil is connected to the generator through a resistor R2. The torque due to the two coils

opposes each other. It consists of three terminals E (earth terminal) and L (line terminal) and G (guard

wire terminal).


25/26


26/26

OPERATION:

When the terminals are open circuited, no current flows through the deflecting coil.

The torque to the controlling coil moves the pointer to one end of the scale. When the terminalsare short circuited, the torque due to the controlling coil and the pointer is deflected to the other

end of the scale i.e. zero mark. In between the two extreme positions the scale is calibrated to

indicate the value of unknown resistance directly. The unknown insulation resistance is the

combination of insulation volume resistance and surface leakage resistance. The guard wire

terminal makes the surface leakage current to bypass the instrument hence only insulation

resistance is measured.

RESULT:

Thus the measured value of the resistance to earth / insulation resistance of the

unknown material is = ----- M

1year lab manual_eee

Documents