ICC ETH-1000, Инструкция по эксплуатации

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8.7.11 Modbus/TCP Client
The Modbus/TCP client driver can be used to access information on any device
which supports the Modbus/TCP server protocol. This driver also supports the
32-bit extension to the Modbus standard (commonly referred to as the
“Enron/Daniel” extension). Similar to other master/client protocol drivers on the
gateway, the Modbus/TCP client driver uses service objects to issue read and
write requests to the Modbus/TCP server device. Modbus/TCP service objects
also make use of an additional gateway construct called a connection object in
order to target Modbus/TCP server devices. A connection object can be thought
of as a communication channel or “pipe” which is created between the gateway
and the Modbus/TCP server device, independent of the service objects that may
later make use of that communication channel to transfer service object requests.
A connection object defines a connection to a specific endpoint (IP address).
Because service objects must always be configured to utilize a specific
connection object, at least one connection object must initially be created before
any service objects can be created. For more information on service objects,
refer to section 8.5.
Each register (input or holding) in a service object is mapped to 2 bytes in the
database (the data type is fixed at 16-bit). Each discrete (input or coil) is mapped
starting at the least-significant bit of the byte specified by the database address
and at each consecutive bit thereafter. For more information on register and
discrete mapping, refer to section 11.12.2.1.3.
To configure the Modbus/TCP client, click on the
Ethernet Configuration tab,
check Modbus/TCP Client in the protocol dropdown menu to enable the driver,
and then click on the Modbus/TCP Client subtab. This section will discuss how
to configure the Modbus/TCP Client .
Scan Rate
This is the time in milliseconds the device will wait between sending requests. If
no additional time is required, set this field to 0.
8.7.11.1 Connection Object Configuration Group
Up to 4 connection objects can be created.
Name
A unique name used for identifying the connection object. Enter a string of up to
16 characters in length.
IP Address
This is the IP address of the Modbus/TCP server to be targeted by the
connection object.