1. ELECTRICAL TECHNOLOGY
Electricity is not a fun but easy to learn.

2. Prepared by,
Mr. Vijay Balu Raskar
CHAPTER NUMBER NAME OF CHAPTER (Polytechnic)
1 D.C. CIRCUITS
2 A.C. FUNDAMENTALS
3 SINGLE PHASE AC CIRCUITS
4 THREE PHASE AC CIRCUITS
5 SINGLE PHASE TRANSFORMERS
6 D.C.MOTORS
7 FRACTIONAL HORSE POWER MOTORS
8 INSTALLATIONS,EARTHING AND
TROUBLE SHOOTING
9 DIFFERENT TYPES OF MOTORS

3. PROTECTION
Fuse
HRC-Fuse
MCB
MCCB
ELCB

4. 
FUSE
•There are two
types.
1. Rewirable / semi-
enclosed type
2. HRC type fuse

6. HRC FUSE

7. Operation of Circuit Breaker
(See the Circuit Diagram on Black
Board)

8. Rating of MCB
Up to 100A
Braking Capacity:- 3KA
Rating of MCCB
Up to 1600A
Braking capacity:- 85KA
Rating of ELCB
30mA for Domestic
100mA for Industrial
300mA for Higher Leakage

9. EARTHING
1.Plate Earthing
2.Pipe Earthing

10. PLATE EARTHING
Material :- Any metal
Earth Plate:- 60CM X 60CM X 3.18mm
Galvanized Plate:- 90CM X 90CM X
6.35mm.
With Layer of salt & coke (Alternate).
Layer thickness will be 15CM in deep

11. PIPE EARTHING
Galvanized iron pipe is used.
Diameter is not less than 38.1mm and
2m in length for ordinery soil and
2.75m for dry.
At top funnel fill with salty water.

12. TROUBLE SHOOTING
It is the process of detecting faults in
the circuit.
Instruments:- Megger, Tester,
Multimeters, test lamp etc.

13. THANKS
YOU