Detcon TP-524D-HRT - Manual (Page 30)

Model TP-524D-HRT
TP-524D-HRT Instruction Manual Rev. 0.3 Page 26 of 48
The HRT Bridge communicates with the TP-524D-HRT sensor through Modbus™. The HRT Bridge reads
the appropriate Modbus™ register and creates the 4-20mA signal from the register reading. This allows the
HRT Bridge complete control of the HART Communications. A red LED Labeled “MODBUS” will blink
when communication with the sensor occurs.
The HART interface has the ability to take the sensor into calibration. If the sensor is taken into calibration
via the HART interface, the HART Communication Protocol will inform the Host that the sensor is in
calibration mode, and will not set a fault. The 4-20mA signal will be set at 2mA. Starting a calibration using
the sensor interface and magnetic tool will also cause the 4-20mA to be set to 2mA.
4.4 Operator Interface
The HRT Bridge provides the ability to interface with the sensor via the HART Interface. The HART
interface Host can be a PC, a Laptop, or several handheld devices such as the Emerson 375 Field
Communicator. Although the displays on each device may be different and the menu names may change, the
information provided should be the same. The HART Interface consists of three basic Menus, each with a
subset of menus or screens:
Device Variables Menu
Primary Variables
Identification
Diagnostics Menu
Device Status
Sensor Status
Device Status Menu
Configuration Setup
Calibration
HART Setup
NOTE: The screen shots shown below are taken from the HART Communication
Foundation SDC625 Reference Host. The user’s screen appearance may be different
depending on the HART host used.
4.4.1 Device Menu
4.4.1.1 Primary Variables
The primary Variable Screen contains the basic information from the sensor and is broken into four basic
sections. None of these variables are changeable, and are directly read from the sensor.