C.2 Connect with ProLink III
A connection from ProLink III to your transmitter allows you to read process data, configure the transmitter,
and perform maintenance and troubleshooting tasks.
C.2.1 Connection types supported by ProLink III
Different connection types are available for connecting from ProLink III to the transmitter. Choose the
connection type appropriate to your network and the tasks you intend to perform.
The transmitter supports the following ProLink III connection types:
•
Service port connections
•
HART/Bell 202 connections
•
Modbus/RS-485 8-bit connections (Modbus RTU)
•
Modbus/RS-485 7-bit connections (Modbus ASCII)
When selecting a connection type, consider the following:
•
Service port connections are specialized Modbus/RS-485 connections that use standard connection
parameters and a standard address that are already defined in ProLink III. Service port connections are
typically used by field service personnel for specific maintenance and diagnostic functions. Use a service
port connection only when another connection type does not provide the functionality you need.
•
Some connection types require opening the wiring compartment or the power supply compartment.
These connection types should be used only for temporary connections, and may require extra safety
precautions.
•
Modbus connections, including service port connections, are typically faster than HART connections.
•
When you are using a HART connection, ProLink III will not allow you to open more than one window at a
time. This is done to manage network traffic and optimize speed.
•
You cannot make concurrent Modbus connections if the connections use the same terminals. You can
make concurrent Modbus connections if the connections use different terminals.
C.2.2 Connect with ProLink III over Modbus/RS-485
You can connect directly to the RS-485 terminals on the transmitter or to any point on the network.
CAUTION
If the transmitter is in a hazardous area, do not remove the transmitter end-cap while the transmitter is
powered up. Removing the end cap while the transmitter is powered up could cause an explosion. To
connect to the transmitter in a hazardous environment, use a connection method that does not require
removing the transmitter end-cap.
Prerequisites
•
ProLink III v3.2 or later installed and licensed on your PC
•
An available serial port or USB port
•
The installation kit appropriate to your connection type (RS-485 or Bell 202, serial port or USB)
•
Adapters as required (for example, 9-pin to 25-pin)
Using ProLink III with the transmitter
Configuration and Use Manual
March 2021
MMI-20020954
168
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