Application Design; Overview; Safety; Accuracy - Honeywell STT700 STT700 User Manual

2.1.

Overview

This section discusses the considerations involved with deploying a Honeywell STT700 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
2.2. Safety

2.2.1. Accuracy

The STT700 SmartLine Temperature Transmitter accurately measures the temperature of a process
and reports the measurement to a receiving device like a controller I/O module. Refer to STT700
Specification, 34-TT-03-19, for complete accuracy specifications.

2.2.2. Diagnostic Messages

The transmitter standard diagnostics are reported in the two basic categories: critical and non-critical
faults. Problems detected as critical diagnostics drive the analog output to the programmed burnout
level for HART and DE. Tables 3 and 4, below, list the diagnostics and how faults are handled by the
STT700 transmitter. Refer to the Troubleshooting section for further details.
Table 3 show specific diagnostics to the transmitter, exclusive of those associated with HART and
DE protocols. HART and DE diagnostic messages are listed and described in the STT700 SmartLine
Temperature Transmitter HART/DE Option User Manual, document number 34-TT-25-18.
See Safety Integrity Level (SIL)
STT700 is intended to achieve sufficient integrity against systematic errors by the manufacturer's
design. A Safety Instrumented Function (SIF) designed with this product must not be used at a SIL
level higher than the statement, without "prior use" justification by the end user or diverse technology
redundancy in the design. Refer to the STT700 Safety Manual, 34-TT-25-20, for additional
information. The DE variant of STT700 is not SIL certified.
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2. Application Design

STT700 Temperature Transmitter User's Manual
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