Minor Project at NIT Calicut.

1. MEASUREMENT AND DISPLAY OF THE MAINS
FREQUENCY USING PIC18F4520/50
B Tech Mini-Project Report
Submitted in partial fulfillment for the award of the Degree of
Bachelor of Technology in Electrical and Electronics Engineering
By
V.RUTHVIK (B100469EE)
V.TARUN TEJ (B100527EE)
P.RAGHU ADITYA (B100813EE)
P.DURGA RAO (B100470EE)
Under the guidance of
Dr G.JAGDANAND
Department of Electrical Engineering
NATIONAL INISTITUTE OF TECHNOLOGY CALICUT
NIT Campus P.O., Calicut - 673601, India
May 2013.

2. CERTIFICATE
This is to certify that the thesis entitled “Measurement and Display of the Mains
Frequency using Pic18f4520” is a bonafide record of the mini-project done by V.RUTHVIK
(B100469EE), V.TARUN TEJ (B100527EE) and P.RAGHU ADITYA (B100813EE)
P.DURGA RAO (B100470EE) under my supervision and guidance, in partial fulfillment of
the requirements for the award of Degree of Bachelor of Technology in Electrical &
Electronic Engineering from National Institute of Technology Calicut for the year 2013.
Dr G.JAGDANAND
(Guide)
Asst. Professor
Dept. of Electrical Engineering
Dr SUSY THOMAS
Professor & Head
Dept. of Electrical Engineering
Place: CALICUT
Date: 2/5/2013

3. ACKNOWLEDGEMENT
During the course of our Mini Project work on the Measurement and Display of the Mains
Frequency using Pic18f4520, we received a lot of help, encouragement and invaluable guidance
from our fellow students and faculty members alike. We would like to thank Dr. G.
Jagadanand, Assistant Professor for agreeing to be our Project Guide and encouraging us to
take up this project. We thank him profusely for guiding us, challenging us to think differently
and motivating us at all times. We would also like to thank Ms. Preetha P, Assistant professor,
our Project Coordinator, and other members of the evaluation panel for their invaluable
suggestions and words of wisdom. We extend our deepest gratitude to our Head of Department,
Dr. Susy Thomas for allowing us the use of the department resources. We also would like to
thank M.tech students for extending their help in the labs whenever needed.

4. ABSTRACT
There are several mains power systems in use around the world. These systems are primarily
characterized by their “voltage” and “frequency”. These characteristics play a very important
role in power systems stability and operation.
As the demand on the electricity supply increases the frequency usually drops. The electricity
suppliers monitor the mains frequency constantly and aim to keep it within allowed tolerances. A
change in the mains frequency has negative effects in some appliances. For example, the pulse
dependent clocks will run slower or faster dependent on mains frequency. Also some losses
acquired in AC machines are dependent on the supply frequency.
The main intention of our project is to build up a circuit/device to measure supply mains
frequency and to log the data acquired in these measurements to understand the variation in
mains frequency in a day by plotting the data against time in a graph.
This circuit involves measurement through a near zero detection circuit and the measurement is
processed by a PIC18f4520 microcontroller. The measured value will be displayed on a LCD
interface.