Moxa ioLogik E1512-M12-CT-T [43/62] Active opc server from pull to push

ioLogik E1500 Series Active OPC Server Utility

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OPC Client/Server creates a common interface to connect to different devices

Active OPC Server—From Pull to Push

When looking up an I/O device’s Modbus table, 19 or more steps are required to create a single tag. The steps

include specifying the IP address, selecting the protocols, and defining the data type. The procedure is repeated

over and over until all the devices and tags are created. It takes about 1 minute for a user with a technical

background to create one tag. But what if there are 400 tags in an OPC system? Not only does it take a long

time to configure such a large number of tags, it also puts a heavy load on the CPU.

OPC also requires the connected I/O devices to use fixed IP addresses. This type of architecture is sometimes

referred to as “pull” technology, because the OPC server always needs to pull data (by “polling”) from the I/O

devices for tag creation, IP connection, and tag status updates.

Moxa’s ioLogik Active Ethernet I/O products offer I/O status reports via TCP/UDP messaging, e-mail, and SNMP

traps. In addition, they now support OPC technology. An ioLogik can automatically generate tags without

requesting any data or even a device’s IP address. All the user needs to do is launch the Active OPC Server

program, and the I/O channels selected by the user will be “pushed” from the ioLogik to the Active OPC Server.