Reading AC signal from a XBee analog input pin

acarduinocurrent measurementdcxbee

I'm trying to use a ACS756SCA-100B – 100A Hall Effect-Based Linear Current Sensor IC (SCT-013-030) with a precision of 20 mV/A.

My objective is to read input voltage coming from the sensor into the XBee Analog input.

I was wondering if that would be possible by making precision half-wave rectifier, to rectify the sensor output into the XBee. I know that even with half-wave I still get a variation, so I guess that's far from perfect…

On the other hand I've seen these type of projects working with arduino, but as far as I understood, it will basically sample the AC wave a number of times and applies the RMS on it afterwards.

Is it possible to use XBee directly or must I process the wave first on a microcontroller?

Best Answer

The analog pins on an Xbee act virtually identically to the analog pins on an Arduino -- they are inputs to a successive approximation analog-to-digital converter. If the ADC performance of the Xbee is sufficient for your application, then you don't need an additional microcontroller (check the Xbee datasheet for this). And yes, you should use a half-wave rectifier or some other means of protecting your input pins, since the current sensor you mention can output negative voltage.