Honeywell STT850 SMARTLINE, User Manual

Page: 15 / 94

Revision 3 STT850
Temperature Transmitter User’s Manual
Page 5
2 Application Design
1.8. Overview
This section discusses the considerations involved with deploying a Honeywell STT850 SmartLine
Temperature Transmitter in a process system. The following areas are covered:

Safety

Input and output data

Reliability

Environmental limits

Installation considerations

Operation and maintenance

Repair and replacement
1.9. Safety
2.1.1 Accuracy
The STT850 SmartLine Temperature Transmitter (Transmitter) measures the temperature of a process
and reports the measurement to a receiving device. Refer to STT850 Specification, 34-TT-03-14.
2.1.2 Diagnostic Messages
Transmitter standard diagnostics are reported in the two basic categories listed in Table 3. Problems
detected as critical diagnostics drive the analog output to the programmed burnout level for HART
and DE. Problems detected as non-critical diagnostics may affect performance without driving the
analog output to the programmed burnout level (for HART and DE only). Informational messages
(not listed in
Table 3 ) report various Transmitter status or setting conditions. The messages listed in
Table 3 are specific to the Transmitter, exclusive of those associated with HART and DE protocols.
HART and DE diagnostic messages are listed and described in the STT850 SmartLine Temperature
Transmitter HART/DE Option User Manual , document number 34-TT-25-06.