User Manual

Commissioning
SmartRadar FlexLine Part No.: 4417.762_Rev07
6 - 102 Service Manual
6.8 Pressure & Density Measurement and Other HART Inputs (FCI-HT)
6.8.1 Introduction
The Field Communication Instrument - HART (FCI-HT) board is a
HART
®1
master module that enables hybrid-signal (both analog +
digital) communication between the FlexConn instrument and a HART
sensor.
ESF07-0014
FIGURE 6-25 The FCI-HT board
The HART protocol is a bi-directional master-slave communication
protocol, which is used to communicate between intelligent field
instruments and host systems.
The FCI-HT board has a planar transformer for galvanic isolation from
the HART bus. See FIGURE 6-25.
LED LE1 is the board’s
[Health] LED. LEDs LE2 and LE3 will be flashing
to indicate activity on the HART bus. LE2 indicates data is being
transmitted (Tx), LE3 indicates data is being received (Rx).
With the HART protocol, an analog 4-20 mA signal can be combined
with a digital Frequency Shift Keying (FSK) signal. See FIGURE 6-26.
1. Highway Addressable Remote Transducer.
LE1
LE2LE3
planar
transformer