SEN0211 voltage output range documentation

Can someone explain the circuit on SEN0211? 

https://wiki.dfrobot.com/Gravity_Analog_AC_Current_Sensor__SKU_SEN0211_

has this text

Interface: Gravity Analog (PH2.0-3P，analog voltage output 0.2-2.8VDC)

I do not see the .2 offset when there is 0 current flowing. I see close to 0 volts. I'm using a 3.3v power source.

Is the Doc wrong or do I have a bad board or ?