Plc Interfaces; Analog Output; A-B Rio; Controlnet And Ethernet Ip - Mettler Toledo IND780 Guia De Instalacion

1.11.3.

PLC Interfaces

The IND780 PLC interface options include analog output, A-B RIO, ControlNet™, DeviceNet™,
EtherNet/IP
1.11.3.1.

Analog Output

The Analog Output option kit includes a dual-channel option board. This board provides two
channels of an isolated 4-20 mA analog signal output for displayed weight, gross weight, rate or
application variables (selected in setup). One or two boards can be installed in the IND780, for a
maximum of four output channels.
The analog option uses a 16-bit D/A converter for a very precise output. The output signals will be
at the lower limit (4 mA) when the value represented is at zero. When the value reaches its
maximum limit, the output signal will increase to the higher limit (20 mA). Any value between zero
and the maximum limit will be represented as a percentage of the output proportional to the
percentage of the value.
1.11.3.2.

A-B RIO

The A-B RIO option enables data exchange by bi-directional communications using the Discrete
Data Transfer or Block Transfer mode. The IND780 Terminal initiates a communication exchange
with the PLC approximately 20 times per second utilizing the Allen-Bradley Discrete Data Transfer
protocol. This communication is a high-speed, real-time message interface between the IND780
Terminal and the PLC for process control. Division, integer, and floating point values are supported.
The IND780 A-B RIO interface also supports Block Transfer mode for transmission of larger
amounts of data. Additional details about this interface can be found in the IND780 PLC Interface
Manual on the documentation CD.
1.11.3.3.

ControlNet and EtherNet IP

The IND780 supports ControlNet communications or EtherNet / IP interface options and the
appropriate driver software.
1.11.3.4.

DeviceNet

DeviceNet is an RS-485 based network using CAN chip technology. This network was created for
bit- and byte-level devices. The network can be configured to run up to 500kbits per second
depending on cabling and distances. Messages are limited to 8 unfragmented bytes. The network
can include up to 64 nodes including the master, which is commonly called the scanner.
1.11.3.5.

Modbus TCP

Modbus TCP is used to establish master-slave/client-server communication between intelligent
devices. It is an open standard network protocol, widely used in the industrial manufacturing
environment. The Modbus TCP protocol takes the Modbus instruction set and wraps TCP/IP around
it. The Modbus TCP protocol is supported by the Ethernet / IP interface board, version 1.32 or
higher.
1-12 METTLER TOLEDO IND780 Installation Guide
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, Modbus TCP, Profibus DP and Profinet.
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