Rockwell Automation 937CU-AIHLP-DC1 HART Loop Converter Installation Instructions - Manual (Page 18)

Connecting a HART Handheld to the Field Device
You have two options for connecting a HART handheld to the field device:

Connection to terminals 22/24 of the isolated barrier.

Connection to the field cables from the isolated barrier to the field device
Transmitting the HART signal using the current outputs of the isolated barrier is not possible.
Description of HART Operations
Dynamic Query of Variables
Universal HART command 3 is used to query dynamic variables from the field device.
This query is done either directly or by activating burst mode.
Burst Mode
Burst mode is the preferred method because this mode guarantees the fastest signal
transmission. The isolated barrier always tries to set the connected field device to
burst mode
The command for burst mode activation is sent to the field device under the
following conditions:

after a restart or

after resetting the isolated barrier after restarting the field device. In the process,
communication between the field device and isolated barrier must have
been reestablished again after a time out.
Bul. 937
C HART Loop Converter Installation Instructions
16