
3
Reference Manual
00809-0200-4728, Rev RA
Section 1: Introduction
April 2015
Introduction
1.2.2 Transmitter overview
The Rosemount 644 Head Mount and Field Mount Temperature Transmitters support the
following features:
HART configuration with Selectable HART revision capability (Revisions 5 or 7)
Accepts either 1 or 2 inputs from a wide variety of sensor types (2, 3, and 4-wire RTD,
Thermocouple, mV and Ohm)
A compact transmitter size with electronics completely encapsulated in protective
silicone and enclosed in a plastic housing ensuring long-term transmitter reliability
Optional Safety Certification Option (IEC 61508 SIL 2)
Optional enhanced accuracy and stability performance
Optional LCD display with extended temperature ratings of -40 °C to 85 °C
Optional advanced LCD display with local operator interface (LOI)
The 644 Head Mount Transmitter is available in two housing materials (Aluminum and
SST) and various housing options that allow for mounting flexibility in a variety of
environmental conditions. The 644 Field Mount is available in an aluminum housing.
Special dual-sensor features include Hot Backup
™
, Sensor Drift Alert, first good,
differential and average temperature measurements, and four simultaneous
measurement variable outputs in addition to the analog output signal
Additional advanced features include: Thermocouple Degradation Diagnostic, which
monitors thermocouple health, and process and transmitter minimum/maximum
temperature tracking
The Rosemount 644 Rail Mount Temperature Transmitter supports the following features:
4-20mA/HART protocol (Revision 5)
Accepts 1 sensor input from a wide variety of sensor types (2, 3, and 4-wire RTD,
Thermocouple, mV and Ohm)
Completely encapsulated electronics to ensure long term transmitter reliability
Refer to the following literature for a full range of compatible connection heads, sensors, and
thermowells provided by Emerson Process Management.
Temperature Sensors and Assemblies Product Data Sheet, Volume 1 (document
number 00813-0100-2654)
Temperature Sensors and Assemblies Product Data Sheet, Metric (document number
00813-0200-2654)
Commentaires sur ces manuels