If you design machines with network-enabled devices from one of the big players in the market, chances are pretty good that they have multiple versions with a range of network protocol capabilities. But not every manufacturer is able to offer the full range. Enter gateways and protocol adapters, which, if anything, are more necessary than ever.
In a survey conducted last month by Industrial Networking, respondents indicated that after reliability, integrating legacy and disparate networks was high on their list of network concerns.
"In my view, it's getting worse, not better," says Phil Marshall, CEO of Hilscher North America, which specializes in network connectivity. "Users were frustrated because every company continued to come out with its own derivatives of networking. Ethernet has just added another physical layer to interconnectivity."
Our survey respondents gave strong preference to EtherNet/IP, with about 65% indicating it was what they used most for control and automation networking.
The main reason for choosing the network that they use? For almost half (44%), it's the one supported by their primary automation supplier.
Marshall doesn't see the situation getting any better. "Each of the market leaders has a vision of how the network complements its control architecture," he says. "So as long as the market leaders have different visions on how the control systems need to work, network needs are going to remain different."
|Standard and Safety
ENX Series AS-Interface Gateways support both Modbus TCP and EtherNet/IP protocols for seamless communication with standard and safety networks in a single gateway. 992 I/O are handled asynchronous to the Ethernet traffic, and the gateways also scan every AS-i node in 150 µs, which enables up to 62 safety e-stops, magnetic switches and safe outputs to be in one safety program.
Three 758 Series I/O-IPC models function as CANopen masters that directly interface with the SAE J1939 protocol. Carrying dual Ethernet ports for Modbus TCP communication, the I/O-IPCs are gateways to Wago's J1939 interface function block that supports large engine/generator efficiency.
|Mod to Mod
MB-Gateway single-port Modbus gateway module converts Modbus TCP to Modbus RTU. The module has an automatic read function with one RJ45 10/100 Mbps Ethernet port and one RS-422/485 two- or four-wire serial port. It supports up to 12 Modbus TCP Client Ethernet connections and up to 128 RTU Server serial connections.
|Gateway to Modbus
EKI-1221D and EKI-1222D gateways provide transparent connectivity between Modbus serial devices and Ethernet-based Modbus TCP equipment. They have built-in Ethernet switches for cascading/daisy-chain connectivity that offers flexible cabling. Cascading connections support Ethernet auto-bypass to prevent accidental power failure in the event one of the Modbus gateways unexpectedly shuts down.
Advantech Industrial Automation
netTAP 100 Gateway supports real-time Ethernet-to-Ethernet connections to bridge all popular real-time Ethernet networks. Supported protocols include EtherNet/IP, Profinet, EtherCat, Modbus TCP, Powerlink and SERCOS III. The standard module is available with master and/or slave protocols. The configuration tool is FDT/DTM-based for fast setup and ease of use.
|Connect to Fiber
Industrial Ethernet media converters convert the Ethernet, via an RJ45 port, to an optical port with SC or ST glass fiber connections, while remaining transparent to other network devices. They have Link Fault Pass-Through (LFP) technology, which uses mechanical relay outputs to alarm on power failure and port breakages on either fiber or Ethernet ports. Redundant power inputs allow for more secure connections.
|EtherNet/IP to DF1|
MGate EIP3000 has one or two EtherNet/IP-to-DF1 ports for connecting DF1 devices and EtherNet/IP devices to A-B PLCs for remote maintenance. It uses ProCOM, which generates four extra virtual serial channels for Ethernet data pass-through and maximum network flexibility, without modifying the existing system, and it supports two IPs—one for each serial port—so EtherNet/IP devices can communicate with two DF1 devices simultaneously.