It provides the knowledge about starting methods of an induction motor and overload protection.

1. BIRLA PROFESSIONAL TRAINING
&
RESEARCH CENTRE
(BPTRC)
Jayant Suthar
15EBKEE039

2.  CONTENTS -
 Introduction of Training Institute
 Objective
 Work Detail
 Low Voltage Control Panel
 Switchgear
 Air Break Contactor
 Overload Protection
 Starting Methods
 Result
 Conclusion
 Reference

3. INTRODUCTION OF TRAINING
INSTITUTE
Birla Professional Training & Research Centre (BPTRC) provides
training in the fields of Electronic & Communication, Electrical
Engineering, Mechanical Engineering and Computer Science.
While becoming industry-ready student gain exposures in
scientific research here. BPTRC has its own Electrical
Demonstration Lab, PLC Automation and Electric Motor Lab
where student learn all the industrial knowledge they would
require while working in an Industry.

4. OBJECTIVE
 Electric Motor & Control Panel
• Hands-on practice on electrical machines and industrial electric
control panels
• Learning international standard terminal marking for electrical motor
generator and phase
• Study different types of motor and their connection arrangement ,
class of insulation, degree of protection etc
 PLC Automation & Electric Motor
• Understand PLC Programming and ladder logic
• Familiarization with variety of ladder logic instructions to create a
complete PLC program on different Allen Bradley & Genie Nx PLC
boards.

5. WORK DETAIL
1. Electric Motor :-
Introduction, Types of Electric Motor, International Standard for
Phase, Electrical Motor Terminal Marking, Types of Connection,
Types of Motor on the basis of Connection, Class of Insulation,
Degree of Protection.
2. Low Voltage Control Panel :-
Electric Panel, Control Panel, Switchgear, Air Break Contactor,
Overload Protection, Starting Methods.
3. Programmable Logic Controller :-
Introduction, Need of PLC, Basic Architecture of PLC, I/O
Modules, PLC Operation Sequence, Types of PLCs, Ladder
Programming, Manufacturer.

6. LOW VOLTAGE CONTROL PANEL
• Electrical Panel consist of power circuit and control circuit.
• Power circuit provides the supply to the machine.
• Control circuit provides the controlling feature and it protect
the machine from any fault using switchgear in its circuit.
• Control circuit are of two types:
(a) Low Voltage Control Panel
(b) High Voltage Control Panel
• Due to high voltage, sparking occur in high voltage control
panel so it is not used.

7. SWITCHGEAR
• Devices which are use for switching, protecting and controlling
in an electrical circuit are known as switchgear. Switchgear
devices are:
(a) Push Button
(b) Contactor
(c) Connector
(d) Bus Bar
(e) Fuse
(f) Switch
(g) Overload Protection

8.  AIR BREAK CONTACTOR
A contactor is an electrically
controlled switch used for
switching a power circuit,
similar to a relay except with
higher current ratings. In air
break contactor, medium is air.
When the coil is excited,
magnetic field produce in the
surrounding due to which the
plunger gets pull down and close
the contact. The coil can be
excited from the same supply.

9.  OVERLOAD PROTECTION
• Overload Protection is used to protect the motor from overload.
• There are three types of overload protection:
1. Thermal Overload
2. Magnetic Overload
3. Module Overload

10. 1. Thermal Overload:
• It is based on inequality
of linear expansion of two
metal.
• Thermal Overload
Protection uses a
Bimetallic Strip is heated
up by heating coil
carrying over current of
the system, it bends and
break the contact.

11. 2. Magnetic Overload:
• The principle of Magnetic
Overload is production of
magneto motive force (mmf)
due to flow of current through
N number of turns.
Mmf = N*i
Here,
N = Number of turns
i = Current flowing through the
turns

12. 3. Module Overload:
• Thermocouple is a sensor
used to measure
temperature.
• Thermocouple R, Y, B are
connected in series in the
circuit as shown in fig.
During overload current
flowing through the circuit
increase and produce heat,
this heat is sense by the
thermocouple (R, Y, B) and
produce maximum voltage
which reached at
transformer winding and
after it trips the circuit.

13. STARTING METHODS
1. Direct On-Line Starter –
• Simple and most inexpensive method.
• It directly connect contact of the motor
to the full supply voltage.
• The starting current is very large,
normally 6 to 8 times the rated current.
• In order to avoid excessive voltage
drop in the supply line due to high
starting current, the DOL starter is
used only for motor with rating less
than 5HP

14. 2. Resistance Starter –
• External resistances are connected in
series with each phase of stator
winding during starting.
• This causes voltage drop across
the resistance so that voltage
available across motor terminal is
reduced and hence the starting
current.
• The starting resistance are gradually
cut out in steps from the stator circuit
as the motor picks up speed when the
motor attends rated speed, the
resistance set to zero value and full
line voltage is applied to motor.

15. 3. Auto Transformer Starter –
• It is provided with number of
tapings.
• The starter is connected to
one particular tapping to
obtain the most suitable
starting voltage.
• A change over switch is used
to connect the auto
transformer in the circuit for
starting

16. 4. Star Delta Starter –
• A three-phase winding of the
motor is connected in the
star at the instant of starting.
In this condition, the motor
takes reduced voltage and
start safely.
• The applied voltage at
starting is 1/√3 times the
line voltage.
• When the motor has picked
up the speed the connection
change to delta by means of
change-over switch or by a
timer. The motor takes rated
voltage and rated current in
running condition.

17. RESULT
I have learnt following things during the training period:
• Electrical Motor: International Standards, Terminal Marking, Class of
insulation, Degree of protection, Types of Connection arrangement &
their technical specification.
• Learn about bearing technology.
• Low voltage control panel and overload protection.
• Concept of interlocking and learned about starting method of
induction motor.
• Learned about PLCs and its Ladder Logic programming.

18. CONCLUSION
To conclude:
• Reading the data sheets of different machines is important in an
industry.
• Rating and working of machine must be known to the engineer before
operating.
• 3phase Induction motor having rating above 5HP requires starting
method.
• Engineers in industry must have knowledge about fuse, switch, ELCB,
auto transformer etc.

19. REFERENCE
• https://bkbiet.ac.in/on-campus-industrial-training/
• https://electrical-engineering-portal.com/star-delta-motor-
starter
• https://www.electrical4u.com/direct-online-starter-or-dol-
starter/
• https://circuitglobe.com/switchgear.html

20. Thank You