www.miinet.com
Moore Industries-International, Inc.
- 110 -
User’s Manual
238-760-00K
May 2019
Functional Safety Dual Input Smart HART® Temperature Transmitter
STZ
SECTION 6
Section 6 - Operation and Maintenance
Operation
Once calibrated, installed, and supplied with the correct power, the STZ begins to operate
immediately. Depending upon environmental conditions, it can be expected to operate
unattended for extended periods of time.
Note:
If you are not getting HART data from the STZ, its HART mode may be set to Off. You
will need to check the HART mode using the FDT/DTM and USB cable (see Section 5 for
details).
STZ Diagnostics
The STZ has a high level of diagnostic capability to continually monitor itself and its inputs.
Whenever the unit diagnoses a failure which compromises the unit operation it will enter failure
mode ie.
Set analog output (AO) to fail mode
Send error message to display (STZ HP)
Send error message to the HART Handheld/DTM
Set device malfunction status bit in HART and set the relevant HART bits in additional status
The unit will enter failure mode when one of the following occurs:
A device diagnostic error (hardware, software, data, communications)
The Device Variable which is mapped to the PV is marked as BAD
There is a Range Alarm error
There is a configuration error in any Device Variable which has been assigned/ mapped to
HART variables, burst messages or STZ HP display
The following provides an overview of the different types of diagnostics. For a full list of status
and diagnostic messages please refer to Status Messages and HART Registers.
Internal diagnostics:
On power up the unit runs through a thorough diagnostic test (RAM, ROM,
CPU etc.) and an initialization process (SYS INIT is displayed on the STZ HP). If any errors are
found, the unit will enter failure mode. Once in operation, the unit continues diagnostic tests in
the background.
Configuration diagnostics:
On power up the stored configuration is validated. If it is invalid,
the unit will enter failure mode. To clear the failure, reset to the factory default configuration, then
configure as appropriate for the application. If the configuration is changed, the unit will check
before running and enter failure mode if it is invalid.
Input diagnostics
: The STZ has extensive hardware diagnostics of sensor input(s) to detect
broken wire, saturation, out of conformance range and linearization errors. In addition, the unit
can be configured to detect sensor corrosion, sensor drift or in/out of range conditions (see
Section 1, Sensor Diagnostics section for more information).
Every Device & Dynamic Variable in the STZ has a quality stamp, per the HART standard. (See
section 1, Tables 1.1 & 1.2 for a list of Device Variables)
