How to build an AC wattmeter?

[roykyn]

I need ideas to build wattmeter.I have these things in mind.
1>I have seen simple RMS wattmeter using Digital Voltmeter using the age old ICL7106/7 chip.I need proper circuit diagram.
2>The new design using Energy Metering IC with Pulse Output ICs.Sounds good but many companies produce these ICs i am in INDIA bangalore.I would like to know IC numbers available in the market.
3>using ADCs its good concept but i need analog conditioner circuit and other supporting circuits. And i also dont know how to convert AC to measurable DC.
4> ant other methods ...

 

[andre_luis]

ac wattmeter

Try :

AD7500 from Analog Devices.
MCP3909 from Microchip.
TMS320 microcontroler from Texas.


Just using 7107, you could not measure real consumption, due power factor may be diffrent from '1'.


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[Giuss]

ac watt meter

Some time ago, I've used the chip ADE7755 from Analog Device with very good results