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wellyboot
- 30th March 2007, 11:56
Did have add this question to someones elses thead, but its probubly better off in this section.

Im new to this forum and have been looking into designing a project that uses a hall effect sensor to measure AC current, (50hz 240v mains AC)
the sensor i have got is CSLA2CD

and has the following datasheet:
http://pdf1.alldatasheet.com/datashe...C/CSLA2CD.html

the sensor can measure upto 72Amps, and has a linear output that will basically track the input waveform eg. AC voltage output
the device outputs half the supply voltage at 0amps, and the output range is 25-75% of the supply voltage.

The range of current i wish to measure is 0 - 50amps

I think the easier solution is to convert the AC voltage to a DC level

Does anyone have a circuit diagram that can inferface the sensor with the A/D input of a PIC eg PIC16F872?

Thanks
Dave

mvs_sarma
- 12th September 2007, 13:41
you may use an isolation transformer ( like a current transformer and the output can be rectified , conditioned and it can be converted by ADC in the chip and a look uptable canperhaps do the rest

dhouston
- 12th September 2007, 16:39
Look at Allegro hall effect current sensors. They provide isolation and output a DC voltage proportional to the current.

http://www.allegromicro.com/en/Products/Categories/Sensors/currentsensor.asp

wellyboot
- 8th March 2008, 20:40
I used my above hall effect sensor, with a precision rectifier circuit, and a smoothing cap conected between the sensor and the pic to get the required DC which apears to work well

Thanks for your responses

Precision rectifier circuit >
http://sound.westhost.com/appnotes/an001.htm