Hart Communication; Hart Device Type Codes - ABB Endura ACA592 Operating Instructions Manual

Endura ACA592
4-electrode conductivity transmitter

9 HART Communication

9 HART Communication
For ease of identification, each HART device features a configurable 8-character HART tag. In addition to
the HART tag, each device has a HART address (set to the default value 0). At this address the device
operates in HART standard communication mode (point-to-point operation).
When an address in the range 1 to 15 is used, the transmitter switches to HART multidrop mode. This
operating mode enables users to connect up to 15 transmitters in parallel to a power supply.
In multidrop mode, an analog output signal that matches the Primary Value is not available. The output
signal in multidrop mode is, basically, a constant 4 mA and is used exclusively for the power supply.
In multidrop mode, sensor or process data information is available as a HART signal only.
In addition to point-to-point and multidrop modes, the third type of HART communication is burst mode.
When Burst Mode is activated, the transmitter transmits a HART telegram containing process information
continuously, (approximately every 500 ms) without prompting by a HART command.
Refer to the Communication level (page 61) for further details of Burst Mode.

9.1 HART Device Type Codes

All HART products contain unique identifiers that specify the device type.
The device type code for ACA592–EC 4-Electrode conductivity transmitter series is: 49 (31 hex).
OI/ACA592/EC–EN Rev. B 73