Drives and Controls Magazine
Distributed I/O system links wired devices to the IIoT
Published:  13 February, 2020

The Californian automation manufacturer Opto 22 has announced an intelliegent distributed I/O system designed to connect traditional wired switches and sensors directly to Ethernet networks, software applications and the cloud, without needing intermediary controls or communications hardware, such as PLCs, PACs or PCs.

The company points out that although wireless sensing devices have started to appear at the “edge”, most I/O switches, sensors and transmitters still use traditional wired connections. Remote I/O usually needs an industrial controller or gateway to send these signals to other systems, limiting their availability to enterprise consumers. The new “first in class” groov RIO system is designed to be installed and operated independently, using embedded software tools and protocols to share data instantly throughout an organisation.

“When we designed groov RIO, we were looking for ways to democratise I/O data, because that’s what the IIoT is all about,” says Opto 22’s vice-president of product strategy, Benson Hougland. “Although groov RIO can be used as remote I/O with our groov Epic system, or another control system, we also wanted it to operate autonomously, facilitating direct connection between I/O signals and databases, business software, or cloud IoT platforms.”

For applications such as data centre infrastructure management (DCIM), warehouse and office security, and remote condition monitoring – applications that need to move real-world signals to on-site or cloud-based software – I/O integration typically requires multiple components and specialised skills.

Electrical and instrumentation engineers are needed to specify a variety of field I/O modules, and to design, install and wire appropriate I/O enclosures. Controls engineers are needed to program the PLCs for signal processing and data collection. Then networking and software engineers are needed to configure the communication gateways and servers that deliver the data to consumers. With so many layers between data production and consumption, these systems also require significant maintenance to ensure robust communications.

Opto 22’s new I/O system addresses these issues and is said to offer the flexibility needed to speed up the integration of IIoT applications. The first version of groov RIO to ship is a standalone, ten-channel, multi-signal, multi-function I/O (called GRV-R7-MM1001-10) that supports 12 different types of field I/O circuits, making it capable of more than 52,000 I/O combinations. Opto 22 says it will simplify module selection and spares management, as well as allowing easy, enclosure-free installation with multiple power options (including 802.3af Power-over-Ethernet), an extended operating temperature range, and UL and Atex approvals for use in hazardous areas.

Opto 22’s Ethernet-based I/O combines multi-signal sensing with PoE-powered edge data processing for instant connections of real-world signals to the IIoT.

Once installed, the groov RIO system can be managed and configured independently using browser-based tools. Per-channel I/O type and signal-processing options eliminate the need for a master controller, while support for network services such as DNS, DHCP, and VPN simplifies connections. Embedded communications options range from data publishing with MQTT Sparkplug, to advanced signal processing, data aggregation, and transactions with databases and Web services, using the low-code Node-Red environment and runtime.

The GRV-R7-MM1001-10 can handle signals including thermocouples, voltage and current inputs, discrete DC inputs and sinking outputs, and Form C mechanical relays. In addition, two channels provide special functions such as pulse counting, on- and off-time totalisation, software latching, frequency measurement, and more. It is compatible with any Modbus/TCP master and with Opto 22’s groov Epic platform.

The groov RIO system can also be used for standard remote I/O for sensing, control, and visualisation. It is due to start shipping in March.