ROC800-Series Instruction Manual
4-32 Input/Output Modules Revised July-2017
4.14 Highway Addressable Remote Transducer (HART
®
) Module
Note: The HART-2 module (labeled HART-2 with black faceplate)
replaces the HART module (with gray faceplate).
The HART-2 module allows a ROC800 to communicate with HART
devices using the HART protocol. The HART-2 module receives
signals from and transmit signals to HART devices. LEDs provide a
visual indication of the status of each HART channel. Refer to Figure 4-
40.
Note: HART Pass-Through requires you to use the HART Pass-
Through license key (FS8KY-6), which provides PlantWeb
®
Smart Remote Automation functionality. This includes the
ability to pass HART data bi-directionally through the network
to AMS
™
Device Manager software.
The module has four input/output channels. The HART-2 module uses
software-configurable switches, which allow you to set each channel as
input or output. When you set a channel as an input, you can configure
it for use in point-to-point or multi-drop mode (which typically connects
to some type of transmitter, such as a temperature reading). When you
configure a channel as an output, it reverts to point-to-point mode only.
The output supports a Digital Valve Controller (DVC). Each channel
has analog input capability intended for diagnostic and primary process
variable measurement.
In multi-drop mode, you can connect up to five HART devices (in
parallel) to each channel. As with the point-to-point mode, digital
communications are superimposed on the analog signal used to power
the HART devices. Each HART device in multi-drop mode requires 4
mA and the current does not represent any measured variable value.
With all four channels in the multi-drop mode, the ROC800 can
support a maximum of twenty HART devices.
A ROC800 equipped with a HART-2 module is considered to be a
HART Host (primary master) interface with a Class 1 Conformance
classification. The HART-2 module can also be configured with
ROCLINK 800 Configuration software for use as a secondary master in
redundant applications.
Most Universal and some Common Practice commands are supported.
For a list of the commands, refer to the ROC800-Series HART Module
technical specification sheet (ROC800:HART2). The supported