What is the difference between traditional, Arc and Memosens sensors?

Traditional sensors provide standard mV output and rely on a separate transmitter or controller to amplify the signal and convert it to an actual reading. 

Arc sensors provide a built-in microtransmitter that can output either 4 - 20mA or Modbus RTU digital communication. 

Finally, Memosens sensors provide a digital signal compatible with all Memosens transmitters and analyzers currently on the market.