WESTINGHOUSE 5X00059G01

Description

Description
HART (Highway Addressable Remote Transducer) is a digital communication
protocol designed for industrial process measurement applications. Field
measurement devices (transmitters) interface a process control system via an analog
4-to-20 mA current loop. HART uses a low-level frequency-shift-keyed sine wave
signal that is superimposed on the standard 4-to-20 mA process measurement
current loop. Since the HART sine wave signal is small and its average value is zero,
the current loop analog 4-to-20 mA signal is not significantly affected by the
presence of the HART signal. Using HART allows a field device to provide more
than one measurement, which is a feature not available when using only the 4-to-20
mA analog current signal.
“Smart” field devices may be described as field devices in which the analog 4-to-20
mA signal, digital communication, and sometimes power, co-exist on the same pair
of wires. The Ovation HART Analog Input (HAI) module is a standard form factor
Ovation I/O module, which will permit Ovation to communicate with HART
devices.
Electronics Module
There is one Electronics Module group for the HART Analog Input Module:
• 5X00058G01 interfaces to eight current loop signals with an input range of 4-
20 mA.
Personality Module
There is one Personality Module group for the HART Analog Input Module.
• 5X00059G01 contains a single printed circuit board assembly with eight fused
two-wire loop-powered or non-fused active-source (four-wire isolated current
output) transmitter inputs.

The Ovation HART Analog Input Module assembly consists of two modules, an
electronics module containing a logic printed circuit board (LHA) and a field
printed circuit board (FHI). The simplified block diagram for the FHI field board is
shown in Figure 11-1. The electronics module is used in conjunction with a
personality module, which contains a single printed circuit board (PHAI).