digital energy meter using PIC 16F676/16F873A

[meetheboss]

Hello , i m in the final year of my electrical engineering and is given a final year project to make a digital energy meter using microcontrollers...

now the idea abt the project comes to me according to the figure below

**broken link removed**

moving towards the project ... i have got the 1st task for power measurement unit.. for which i need to design the circuitory..

my external examiner has set following limitations in the circuit.

1. No CT & PT to be used.
2. PIC 16F676/16F873A to be used.
3. No energy measuring ICs to be used.

now i have devised to make a circuit to convert a single phase line (220v 50Hz) to 5volts ...

**broken link removed**

but i need to know how to convert this to dc 5volts and then fed to ADC..

secondly i m not able to think abt an ac current measurement circuit which would be scaled for the dc level to be fed to ADC .

thirdly how should i decide which ADC to be used

 

[cktlover]

Am also doing the same project! Plz guide me as to where shld i start from?

 

[rajudp]

you have to read volt an current for power measurement.

check for ac volt measuring circuit

 

[Jack// ani]

thirdly how should i decide which ADC to be used

There is in-built ADC in both of the PICs you mentioned above, you can use it.

you have to read volt an current for power measurement.

check for ac volt measuring circuit

There is no relevant information in the link you provided.

 

[rajudp]

edited the post sorry for the error
schematics of ac volt meter


topic


hope this will help you

 

[cktlover]

Am getting as to how to go for making AC voltmeter but what abt energy meter? Am i to design a voltmeter then ammeter and then go 4 power measurement? Thnx a lot!

Best Regards!

 

[rajudp]

you are using LCD or seven segment for display, if seven segment better go for 16f873 because of more I/O pins. you can measure current using the same pic and calculate the power. i just give the circuit only to show how ac volt can measure with simple resistor divide methode

 

[meetheboss]

you are using LCD or seven segment for display, if seven segment better go for 16f873 because of more I/O pins. you can measure current using the same pic and calculate the power. i just give the circuit only to show how ac volt can measure with simple resistor divide methode

i will be using lcd display ... voltage is not the problem it can be done by a voltage divider but current measurement is a real issue

 

[rajudp]

hope this will help you

 

[rajudp]

or you can use asc712 type hall effect current sensor IC

 

[4S7thilak]

I'm looking for PIC16F676 DC voltmeter with 7segment display circuit and the assembly code to study. Can someone help?
Thanks
4S7

 

[cktlover]

Attached is a schematic of Digital Energy meter as available on the site:
www.enerjar.net
Now working on the code to convert Analog input to digital, I've attempted this (am using PIC 16F877A)

TRISA=%11110000 '2 set 4 bits of PortA
TRISB=%00000000
TrisC=%00000000
TRISD=%00000000
DEFINE ADC_BITS 4
DEFINE ADC_CLOCK 3
DEFINE ADC_SAMPLEUS 100
ADCON1=%11110000    ' To set 4 bits of the converter
ABC:
ADCIN 0,B0    ' To send the analog i/p at 0th location to B0
                   'Will add aftwards as to what to do with the info in B0
PAUSE 10
GOTO ABC

Kindly some1 tell me if am heading for the right thing?