GE Druck DPI 620, User Manual, Page: 69 / 84

[EN] English - K0449 HART
®
device operations 8-1
Chapter 8: HART
®
device operations
8.1 Introduction You can use the DPI 620 calibrator to communicate with
devices that use the HART protocol:
•
The Universal and Common Practice commands specified
in HART revision 5 to 7.
This section includes procedures to use the HART functions
available in the calibrator.
Before you start:
•
Read and understand the “Safety” section.
•
Do not use a damaged instrument.
Note: Use only original parts supplied by the manufacturer.
8.2 About HART
The HART (Highway Addressable Remote Transducer)
protocol uses a digital signal on top of a standard 4 - 20 mA
current loop to get data to and from a HART enabled field
device. These operations are typical:
•
read the primary variable and the analogue output
•
read the device serial number, type and supplier
•
get calibration data (upper and lower range values, sensor
limits, calibration date)
•
do status and fault finding checks
•
change the device configuration (range, units, damping)
One HART device (a master device) starts and controls the
communications with commands. The field device (a slave
device) uses each command to make a change and/or send
data back.
Two master devices are permitted: a primary master (usually
the main control and monitor system), and a secondary master
(usually a handheld communicator). The DPI 620 calibrator
operates as a secondary master.