What is the typical HART communication speed?

What is the typical HART communication speed?

• A. 300 bits per second
• B. 9600 bits per second
• C. 2400 bits per second
• D. 1200 bits per second

Answer: (D)

HART sends digital data by modulating the existing 4-20 mA loop with frequency-shift keying, so the digital messages ride on top of the analog signal. The rate at which bits are transmitted is 1200 bits per second. This slower speed is chosen to keep the digital signaling reliable over long cables and in noisy industrial environments without disturbing the measured analog current. Higher data rates are not part of the standard HART specification, so 1200 bits per second remains the typical speed.

HART sends digital data by modulating the existing 4-20 mA loop with frequency-shift keying, so the digital messages ride on top of the analog signal. The rate at which bits are transmitted is 1200 bits per second. This slower speed is chosen to keep the digital signaling reliable over long cables and in noisy industrial environments without disturbing the measured analog current. Higher data rates are not part of the standard HART specification, so 1200 bits per second remains the typical speed.