EC: STZ functional safety dual input smart HART temperature transmitter

Safety - Process safety, intrinsic safety: The STZ functional safety dual input smart HART temperature transmitter is a SIL 3-capable temperature transmitter that reduces process interruptions and is certified by exida for use in safety instrumented systems where dangerous processes occur. This is a Control Engineering 2016 Engineers’ Choice finalist.

October 15, 2015

The STZ was designed and built from the ground up to ensure conformance with strict IEC 61508:2010 standards for safety-related applications and has been certified by exida after rigorous evaluation.

It has dual sensor input that reduces process interruptions. Backup and fail-over orotection allows either of the sensors or inputs to be designated as the primary measurement, with the secondary input acting as the backup sensor in case of primary sensor failure. The dual sensor input also allows for average and differential measurements along with high-select and low-select options.

The STZ also includes features designed for smarter control and monitoring:

  • Sensor drift and corrosion detection that checks and alerts users when the sensor is drifting out of a preset range or when the resistance due to corrosion exceeds set parameters
  • Smart range alarms with four HART alarms that detect when the variable is within or outside of user preset limits
  • A high availability option that helps prevent spurious trips or nuisance alarms in safety instrumented systems
  • Input simulation capability simulates a real input, allowing users to test the AO or any HART diagnostic and range alarms—which assists in proof test procedures.

The STZ is HART 7 compliant with exception-based reporting and dynamic variable mapping. It is HART and DTM programmable with user-oriented basic configuration for fast and accurate setup. Utilizing the HART DD, it can be configured and interrogated on the 4- to 20-mA loop via any HART handheld communicator or HART compatible host. To prevent unauthorized or accidental reconfiguration of the STZ while it’s performing its safety function, it has an added security feature to allow users to set HART communication into a “read only” or “off” mode. Users can program or monitor the transmitter with any FDT compliant host or program such as PACTware using the STZ DTM.

Moore Industries-International Inc.,