AB81
Kirchoff’s Law
(Kirchoff’s Current Law &
Kirchoff’s Voltage Law)
Analog Lab
Experiment Board
Ver. 1.0
QUALITY POLICY
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Research, Modern manufacturing techniques and
continuous improvement in Quality of the products
and Services with active participation of employees.
An ISO 9001: 2000 company
94-101, Electronic Complex, Pardesipura INDORE-452010, India.
Tel.: 91-731-2570301 Fax: 91-731-2555643
Email: info@scientech.bz Web: www.scientech.bz
AB81
Scientech Technologies Pvt. Ltd.
2
AB81
Kirchoff’s Law
(Kirchoff’s Current Law & Kirchoff’s Voltage Law)
AB81
TABLE OF CONTENTS
1.Introduction
4
2. Theory
6
3.Experiments
•
Experiment 1
To study the Kirchoff’s Current Law.
8
•
Experiment 2
To study the Kirchoff’s Voltage Law.
10
4.
Warranty
12
5.
6.
7.
List of Service Centers
List of Accessories With AB81
Notes
13
14
15
Scientech Technologies Pvt. Ltd.
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AB81
INTRODUCTION
AB81 is a compact, ready to use Kirchoff’s Law (Kirchoff’s Current
Law & Kirchoff’s Voltage Law) experiment board. This is useful for
students to study Kirchoff’s current Law and Kirchoff’s voltage Law. It can
be used as stand alone unit with external DC power supply or can be used
with Analog Lab which has built in DC power supply, AC power supply,
function generator, modulation generator, continuity tester, toggle switches
and potentiometer.
List of Boards :
Model
AB01
AB02
AB03
AB04
AB05
AB06
AB07
AB08
AB09
AB10
AB11
AB14
AB15
AB16
AB17
AB18
AB19
AB20
AB21
AB22
AB23
AB25
AB28
AB29
AB30
AB31
AB32
AB33
Name
Diode characteristics (Si, Zener, LED)
Transistor characteristics (CB NPN)
Transistor characteristics (CB PNP)
Transistor characteristics (CE NPN)
Transistor characteristics (CE PNP)
Transistor characteristics (CC NPN)
Transistor characteristics (CC PNP)
FET characteristics
Rectifier Circuits
Wheatstone Bridge
Maxwell’s Bridge
Darlington Pair
Common Emitter Amplifier
Common Collector Amplifier
Common Base Amplifier
Cascode Amplifier
RC-Coupled Amplifier
Direct Coupled Amplifier
Class a Amplifier
Class B Amplifier (push pull emitter follower)
Class C Tuned Amplifier
Phase Locked Loop (FM Demodulator & Frequency
Divider / Multiplier)
Multivibrator ( Mono stable / Astable)
F-V and V-F Converter
V-I and I-V Converter
Zener Voltage Regulator
Transistor Series Voltage Regulator
Transistor Shunt Voltage Regulator
Scientech Technologies Pvt. Ltd.
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AB81
AB41
AB42
AB43
AB44
AB45
AB51
AB52
AB53
AB54
AB56
AB65
AB66
AB67
AB68
AB80
AB82
AB83
AB84
AB85
AB88
AB89
AB90
AB91
AB92
AB93
AB96
AB97
AB101
AB102
AB106
Differential Amplifier (Transistorized)
Operational Amplifier (Inverting / Non-inverting /
Differentiator)
Operational Amplifier (Adder/Scalar)
Operational Amplifier (Integrator/ Differentiator)
Schmitt Trigger and Comparator
Active filters (Low Pass and High Pass)
Active Band Pass Filter
Notch Filter
Tschebyscheff Filter
Fiber Optic Analog Link
Phase Shift Oscillator
Wien Bridge Oscillators
Colpitt Oscillator
Hartley Oscillator
RLC Series and RLC Parallel Resonance
Thevenin’s and Maximum power Transfer Theorem
Reciprocity and Superposition Theorem
Tellegen’s Theorem
Norton’s theorem
Diode Clipper
Diode Clampers
Two port network parameter
Optical Transducer (Photovoltaic cell)
Optical Transducer (Photoconductive cell/LDR)
Optical Transducer (PhotoTransistor)
Temperature Transducer (RTD & IC335)
Temperature Transducer (Thermocouple)
DSB Modulator and Demodulator
SSB Modulator and Demodulator
FM Modulator and Demodulator
………… and many more
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AB81
THEORY
Kirchoff's two laws reveal a unique relationship between current, voltage,
and resistance in electrical circuits that is vital to performing and
understanding electrical circuit analysis. Many circuits are extremely
complex and cannot be solved with Ohm's Law. These circuits have many
branches which would make the use of Ohm's Law impractical or
impossible.
Through experimentation in 1857 the German physicist Gustav Kirchoff
developed methods to solve complex circuits. Kirchoff developed two
conclusions, known today as Kirchoff’s Laws.
Law 1: The sum of the voltage drops around a closed loop is equal to
the sum of the voltage sources of that loop (Kirchoff's Voltage Law).
Law 2: The current arriving at any junction point in a circuit is equal
to the current leaving that junction (Kirchoff’s Current Law).
Kirchoff’s two laws may seem obvious based on what we already know
about circuit theory. Even though they may seem very simple, they are
powerful tools in solving complex and difficult circuits.
Kirchoff’s Voltage Law :
Kirchoff’s first law is also known as his “voltage law”. The voltage law
gives the relationship between the “voltage drops” around any closed loop
in a circuit, and the voltage sources in that loop. The total of these two
quantities is always equal. In equation form: Esource = E1 + E2 + E3 + etc. =
I1R1 + I2R2 + I3R3 + etc. Σ source = where the symbol S (the Greek letter
sigma) means “the sum of”.
Kirchoff’s voltage law can be applied only to closed loops (Fig.1).
Fig. 1
A closed loop must meet two conditions:
1.
It must have one or more voltage sources.
2.
It must have a complete path for current flow from any point, around
the loop, and back to that point.
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AB81
Kirchoff’s Current Law :
Kirchoff’s second law is called his current law and states: ‘‘At any junction
point in a circuit, the current arriving is equal to the current leaving.” Thus,
if 15 amperes of current arrives at a junction that has two paths leading
away from it, 15 amperes will divide among the two branches, but a total of
15 amperes must leave the junction.
We are already familiar with Kirchoffs current law from parallel circuits,
that is, the sum of the branch currents is equal to the total current entering
the branches, as well as the total current leaving the branches
|in = |Out 1 + |Out2
|in 1 + |in 2 + |in 3 = |Out
Fig. 2
While applying the above two laws for circuit calculations, plenty of errors
can occur unless proper algebraic signs are given both to IR drops and
battery EMFs.
We will follow a very simple sign convention, which would apply equally
to IR drops and battery EMFs.
A rise (or increase) in voltage would be considered positive and given a +ve
sign and a fall (or decrease) in voltage would be considered negative and
hence given a −ve sign.
For Battery EMF while going round a loop if we go from the negative to
positive terminal of a battery, there is a rise in potential, hence this EMF
should be given +ve sign.
For IR drops on resistor if we go through a resistor in the same direction as
its current, then there is a fall or decrease in potential for the same reason
that current always flows from a higher to a lower potential.
Hence this IR drop should be taken −ve. However, if we go around the loop
in a direction opposite to that of the current, i.e., if we go upstream, there is
a rise in voltage. Hence this IR drop should be taken as positive.
So, the algebraic sign of IR drop across a resistor depends on the direction
of current in that resistor.
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AB81
EXPERIMENT 1
Objective :
To verify Kirchoff’s Current Law.
Apparatus required :
1.
Analog board AB81.
2.
DC power supplies +12V from external source or ST2612 Analog
Lab.
3.
Digital multimeter.
4.
2 mm patch cords.
Circuit diagram :
Circuit used to study Kirchoff’s Current Law is shown in Fig 3.
Fig. 3
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AB81
Procedure :
•
Connect +12V dc power supplies at their indicated position from
external source or Analog Lab.
1.
Connect 2mm patch cord between test point 1 & 2, 3 & 4, 5 & 6, 7 &
8, 9 & 10, 11 &12, 13 & 14, 15 & 16.
2.
To test KCL at node B
3.
Measure incoming current I in between test point 1 & 2 by replacing
2mm patch cord with an Ammeter.
4.
Reconnect patch cord between test point 1 & 2.
5.
Measure outgoing current I1 between test point 7 & 8 by replacing
2mm patch cord with Ammeter.
6.
Reconnect patch cord between test point 7 & 8.
7.
Measure outgoing current I2 between test point 3 & 4 by replacing
2mm patch cord with an Ammeter.
8.
Reconnect patch cord between test point 3 & 4.
4.
Check whether the sum of incoming current/currents is equal to the
sum of outgoing current/currents.
5.
Repeat above procedure for junction point C, D, G, H, I and there
corresponding incoming and outgoing current/currents.
.
Result :
_________ (Yes/No), the sum of incoming current/currents is equal to the
sum of out going current/currents for all junction point.
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AB81
EXPERIMENT 2
Objective :
To verify Kirchoff’s Voltage Law.
Apparatus required :
1.
Analog board of Kirchoff’s Laws.
2.
DC power supplies +12V from external source or Analog Lab.
3.
Digital multimeter.
4.
2 mm patch cords.
Circuit diagram :
Circuit used to study Kirchoff’s Voltage Law is shown in Fig 4.
Fig. 4
Scientech Technologies Pvt. Ltd.
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AB81
Procedure :
•
Connect +12V dc power supplies at their indicated position from
external source or Analog Lab ST2612.
1.
Connect 2mm patch cord between test point 1 & 2, 3 & 4, 5 & 6,
7 & 8, 9 & 10, 11 & 12, 13 & 14, 15 & 16.
2.
To test KVL in loop ABIJ.
3.
Measure current Iin flowing through resistor of 330E with the help of
Ammeter by replacing 2mm patch cord between test point 1 & 2 with
an Ammeter.
4.
Reconnect patch cord between test point 1 & 2.
5.
Measure current I1 flowing through resistor of 100E with the help of
Ammeter by replacing 2mm patch cord between test point 7 & 8 with
an Ammeter.
6.
Reconnect patch cord between test point 7 & 8.
7.
Measure current Iout flowing through resistor of 100E with the help
of Ammeter by replacing 2mm patch cord between test point 15 &
16 with an Ammeter.
8.
Reconnect patch cord between test point 15 & 16.
9.
Calculate different IR drop in the selected loop (Check that the Sign
of IR drop should be given after considering direction on current)
10.
Measure the sum of IR drop with there sign.
11.
Equate the sum of all IR drop with there sign and sum of the source
voltage of that particular loop.
12.
In case of No voltage source in loop take the sum of all voltage
source equal to zero.
13.
Repeat above procedure for loop BCHI, CDGH, DEFG …………….
by measuring current flowing through different resistor in the loop.
Result :
Scientech Technologies Pvt. Ltd.
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AB81
________(Yes/No), The sum of IR drop in all of the loop is equal to the
source voltage of that loop coming and is equal to zero in case of loop with
No voltage source.
Scientech Technologies Pvt. Ltd.
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AB81
WARRANTY
1) We guarantee the instrument against all manufacturing defects during
24 months from the date of sale by us or through our dealers.
2) The guarantee covers manufacturing defects in respect of indigenous
components and material limited to the warranty extended to us by the
original manufacturer, and defect will be rectified as far as lies within
our control.
3) The guarantee will become INVALID.
a) If the instrument is not operated as per instruction given in the
instruction manual.
b) If the agreed payment terms and other conditions of sale are not
followed.
c) If the customer resells the instrument to another party.
d) Provided no attempt have been made to service and modify the
instrument.
4) The non-working of the instrument is to be communicated to us
immediately giving full details of the complaints and defects noticed
specifically mentioning the type and sr. no. of the instrument, date of
purchase etc.
5) The repair work will be carried out, provided the instrument is
dispatched securely packed and insured with the railways. To and fro
charges will be to the account of the customer.
DISPATCH PROCEDURE FOR SERVICE
Should it become necessary to send back the instrument to factory please
observe the following procedure:
1) Before dispatching the instrument please write to us giving fully details
of the fault noticed.
2) After receipt of your letter our repairs dept. will advise you whether it
is necessary to send the instrument back to us for repairs or the
adjustment is possible in your premises.
Dispatch the instrument (only on the receipt of our advice) securely packed
in original packing duly insured and freight paid along with accessories and
a copy of the details noticed to us at our factory address..
Scientech Technologies Pvt. Ltd.
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AB81
LIST OF SERVICE CENTERS
1. Scientech Technologies Pvt. Ltd.
90, Electronic Complex
Pardesipura,
INDORE – 452010
2. Scientech Technologies Pvt. Ltd.
First Floor, C-19,
F.I.E., Patparganj Industrial Area,
DELHI – 110092
3. Scientech Technologies Pvt. Ltd.
New no.2, Old no.10, 4th street
Venkateswara nagar, Adyar
CHENNAI – 600025
4. Scientech Technologies Pvt. Ltd.
202/19, 4th main street
Ganganagar,
BANGALORE- 560032
5. Scientech Technologies Pvt. Ltd.
8,1st floor, 123-Hariram Mansion,
Dada Saheb Phalke road,
Dadar (East),
MUMBAI –400014
6. Scientech Technologies Pvt. Ltd.
988, Sadashiv Peth,
Gyan Prabodhini Lane,
PUNE – 411030
7. Scientech Technologies Pvt. Ltd
SPS Apartment, 1st Floor
2, Ahmed Mamoji Street,
Behind Jaiswal Hospital,
Liluah, HOWRAH-711204 W.B.
8. Scientech Technologies Pvt. Ltd
Flat No. 205, 2nd Floor,
Lakshminarayana Apartments
‘C’ wing, Street No. 17,
Himaytnagar,
Scientech Technologies Pvt. Ltd.
Ph : (0731) 2570301
Email : info@scientech.bz
Ph : (011) 22157370, 22157371
Fax : (011) 22157369
Email : ndel@scientech.bz
Ph : (044) 42187548, 42187549
Fax : (044) 42187549
Email : chennai@scientech.bz
Ph : (080) 51285011
Fax : (080) 51285022
Email : bangalore@scientech.bz
Ph : (022) 56299457
Fax : (022) 24168767
Email : stplmum@scientech.bz
Ph : (020) 24461673
Fax : (020) 24482403
Email : pune@scientech.bz
Ph : +913355266800
Email : kolkata@scientech.bz
Ph : (040) 55465643
Email : hyd@scientech.bz
14
AB81
HYDERABAD- 500029
LIST OF ACCESSORIES
1.
2mm Patch cord (red) .........................................................1 Nos.
2.
2mm Patch cord (black) ......................................................1 Nos.
3.
2mm Patch cord (blue) ........................................................7 Nos.
Scientech Technologies Pvt. Ltd.
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NOTES
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AB81
NOTES
Scientech Technologies Pvt. Ltd.
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