Emerson Rosemount 644 FOUNDATION, Справочное руководство

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1
Reference Manual
00809-0400-4728, Rev CA
Introduction
September 2018
Introduction
Section 1 Introduction
1.1 Using this manual
The sections in this manual provide information on installing, operating, and maintaining the
Rosemount
™
644 Pressure Transmitter. The sections are organized as follows:
Section 2: Configuration provides instruction on commissioning and operating transmitters.
Information on software functions, configuration parameters, and online variables is also included.
Section 3: Installation contains mechanical and electrical installation instructions, and field upgrade
options.
Appendix A: Specifications and Reference Data supplies reference and specification data, as well as
ordering information and contains intrinsic safety approval information, European ATEX directive
information, and approval drawings.
Appendix B: Foundation
™
Fieldbus Block Information provides information regarding the function blocks
1.1.1 Transmitter
Features of the Rosemount 644 include:

Accepts inputs from a wide variety of sensors

Configuration using F
OUNDATION
Fieldbus Protocol

Electronics that are completely encapsulated in epoxy and enclosed in a metal housing, making the
transmitter extremely durable and ensuring long-term reliability

A compact size and two housing options allowing mounting flexibility for the control room or the field
Refer to the following literature for a full range of compatible connection heads, sensors, and
thermowells provided by Emerson.

Temperature Sensors and Assemblies Product Data Sheet , Volume 1

Temperature Sensors and Assemblies Product Data Sheet , Volume 2
1.2 Considerations
1.2.1 General
Electrical temperature sensors such as RTDs and thermocouples produce low-level signals proportional
to their sensed temperature. The Rosemount 644 converts the low-level sensor signal to a standard
4–20 mA dc, or digital F
OUNDATION
Fieldbus signal that is relatively insensitive to lead length and
electrical noise. This signal is then transmitted to the control room via two wires.
1.2.2 Commissioning
The transmitter can be commissioned before or after installation. It may be useful to commission it on
the bench, before installation, to ensure proper operation and to become familiar with its functionality.
Make sure the instruments in the loop are installed in accordance with intrinsically safe, FISCO, or
non-incendive field wiring practices.