www.miinet.com
Moore Industries-International, Inc.
- 11 -
User’s Manual
238-760-00K
May 2019
Functional Safety Dual Input Smart HART® Temperature Transmitter
STZ
SECTION 1
Table 1.2.
Dynamic Variables
Dynamic Variable Description
Dynamic Variable
PCT
Percent Of Output Range (PV scaled to 0-100%)
AO
Analog Output/ Loop Current
PV
Primary or Process Variable
SV
Secondary Variable
TV
Tertiary Variable
QV
Quaternary Variable
To select the measurement which appears on the Analog Output, the relevant Device Variable
must be assigned to the PV (Primary or Process Variable). By default, Sensor 1 (SEN1) is
assigned to the PV.
Note:
To use a calculated Device Variable, both sensors’ engineering units (EGU) must be
compatible (i.e. the same or both temperature units). If a calculated Device Variable has
different engineering units (EGU) from the Sensors’ EGU, scaling will need to be used to
change the units.
HART Broadcast Messaging (Burst Mode)
The STZ supports enhanced broadcast messaging more commonly referred to as burst mode.
When set to burst mode, the STZ will proactively send out messages instead of waiting for the
host to request them. This enables event driven communication (high, low, deviation of signal or
change in status) and/or timed communication (every 20 seconds) to the host. Up to 3 different
burst messages may be configured in the STZ. Please see section 4 for more information on
burst mode configuration
Note:
When using burst mode in the STZ, the host must also be configured to communicate in
burst mode.
HART Modes
The STZ has an added security feature to allow users to set HART communication into a Read
Only or Disable mode. In Read Only mode, the STZ responds to HART7 commands to access
device variables and diagnostic status but does not allow any changes to be made to the unit
configuration. In Disable mode, all HART messages sent to the unit are ignored and no HART
messages are sent from the unit.
These modes will prevent unauthorized or accidental reconfiguration of the STZ while it’s
performing its safety function. HART communication is in Full Access mode by default and the
mode can only be changed using FDT/DTM with the USB communication cable connected to the
STZ. The HART mode cannot be read or changed using HART communication.