Hardy HI 6500 Series - Manual (Page 46)

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If there is a problem with the connection between the PLC and the HI 6500, recheck the IP
addresses used and the setup parameters in the PLC I/O configuration.
The read-only Connected entry confirms that the 6500 is connected to the network. If the
instrument is not connected to the network, a message appears saying “Not Connected.”
Check the EtherNet/IP connection at the rear of the instrument to make sure it is securely
fastened to the EtherNet/IP port.
Modbus TCP
MODBUS is an application layer messaging protocol used to support client / server
communications between devices connected on different types of buses or networks. All
the HI 6500 series units have Modbus TCP built-in..There is no setup in the HI 6500 unit
to configure the Modbus TCP.
Refer to the I/O tables in previous section for an understanding of the data and format for
the Modbus TCP communications.
If you do not have a Modbus PLC available to test the Modbus communications, then you
can download the Hardy Modbus Link test software from the Hardy Web site at
http://www.hardysolutions.com. This program can be found currently on the HI 4050
products page under the Docs & Programs tab.
Installing the Hardy Modbus-Link Test Package: If you do not have a PLC or other
client, Hardy has provided the Hardy Modbus-Link Client to test communications with the
HI 6500 unit. This client package only communicates with the unit and is not a full
communications package. If you have problems with this test, contact Hardy Technical
Support. Double click the Hardy Modbus-Link .exe file to install the software on your PC.
Upon completion, a Hardy Modbus-Link icon appears on your Desktop.
Modbus services are specified by function codes that are elements of MODBUS request /
reply PDUs. MODBUS is implemented for the HI 6500 using TCP/IP over Ethernet. The
Client/Server definitions are as follows:
• Client - The module asking for data.
• Server - The module providing the data.
NOTE MODBUS is positioned at level 7 of the OSI model and is accessed at a reserved system
port 502 on the TCP/IP stack. It will support communication with up to 10 different hosts
(sockets).
Configuring MODBUS