HART

HART stands for Highway Addressable Remote Transducer. The HART protocol makes use of the Bell 202 FSK (Frequency Shift Keying) standard to superimpose digital communication signals at a low level on top of a 4-20mA control signal.This enables two-way field communications to take place and makes it possible for additional information to be communicated beyond the normal process variable to and from a SMART field instrument.