Hart Communicator; Figure 3 Typical Communication Interface - Honeywell ST 3000 User Manual

HART Communicator

Transmitter adjustments
Except for optional local zero and span adjustments, the ST 3000 has no physical adjustments. You need a
HART communicator to make any adjustments in a ST 3000 with the HART communications option.
Transmitter operator interface
The HART communicator (Model 275) is connected to the loop wiring of the ST 3000 transmitter for direct
communication with the transmitter. The hand-held communicator "talks" with a transmitter through serial
digital signals over the 4 to 20 milliampere line used to power the transmitter. A request/response format is
the basis for the communication operation. The transmitter's microprocessor receives a communication
signal from the communicator, identifies the request, and sends a response message.
Figure 3 shows a simplified view of the communication interface provided by the communicator.
ST 3000
Communicator Purpose
The communicator allows you to adjust transmitter values, or diagnose potential problems from a remote
location such as the control room. You use the communicator to:
•
Configure: Define and enter the transmitter's operating parameters.
•
Monitor: Read the input pressure to the transmitter in engineering units and the transmitter's output in
milliamperes or percent.
•
Display: Retrieve and display data from the transmitter or the communicator's memory.
•
Check current output: Use the transmitter to supply the output current desired for verifying analog
loop operation, troubleshooting, or calibrating other components in the analog loop.
•
Troubleshoot: Check status of transmitter operation and display diagnostic messages to identify
transmitter, communication, or operator error problems.
ATTENTION
Throughout this manual, procedures are given on how to use the HART communicator to
configure, operate and troubleshoot the ST 3000 transmitter. Keystrokes and screen displays
for the HART communicator are referenced in these procedures. However, additional
information on communicator operation is found in the product manual supplied with the
communicator.
10/05
1— Introduction - First Time Users Only - HART Communicator
Request
4 to 20 mA line
Response

Figure 3 Typical Communication Interface

ST 3000 HART Transmitter Release 300 User Manual
HART
Communicator
Power
Supply and
Receiver
7