Detcon 700 HRT Bridge - Manual (Page 5)

HRT Bridge
700 Sensor HRT Bridge IM Rev. 0.2 Page 1 of 18
1.0 Description
The HRT Bridge PCA is a bi-directional digital communication interface that provides data communication
between the Model 700 sensors and HART
® -enabled devices. The HART ® (Highway Addressable Remote
Transducer) Communication Protocol is a standard for sending and receiving digital information across analog
wires between smart devices and a control host or monitoring system. A host can be any software application
from a technician's hand-held device or laptop to a plant's process control, asset management, safety or other
system using any control platform.
The HART
Communication Protocol makes use of the Bell 202 Frequency Shift Keying (FSK) Standard to
superimpose digital communication signals on the 4-20mA signal utilized by the Model 700 sensors. This
enables two-way communication and makes it possible for additional information to be transferred to and from
the sensor.
Figure 1 HRT Bridge PCA
The HRT Bridge PCA communicates with the Model 700 sensors via its Modbus™ interface and transfers that
information to the HART
Communication Protocol along with the 4-20mA Signal. This provides the ability
for a HART Host System to communicate with the Model 700 sensor. This communication includes the
ability for the Host to:
• Configure or re-configure the sensor
• Perform sensor diagnostics
• Troubleshoot the sensor
• Read additional information from the sensor
• Determine the sensor’s health and status