Willowglen Systems' new line of Unisen scaleable remote terminal units (RTU) have been designed from the ground up in response to customer requests for systems that are easy to use and upgrade and are backward-compatible. They range from 32 points to 2000 points in a single RTU and come with an integrated, web-based, secure management interface and report engine and import/export capability using Microsoft Office tools. "Make it easy" was Willowglen's goal in designing the Unisen.
Make it easy for the local technician in charge of maintaining the RTU. The Unisen line is compatible with any standard web browser. This means that any laptop will work, running any web browser, including Explorer. Software doesn't have to be installed ahead of time.
Make it easy for the engineer in charge of configuring the RTU. Tasks such as creating new I/O points or changing alarm settings can be done via the browser interface. Configuration can be done using standard spreadsheets. Wizards walk users step by step through the configuration process.
Make it easy for existing customers to upgrade. Simply by replacing the intelligent subsystem controller card, all the new features of the Unisen RTUs become available. They were designed to be compatible with the 30 different existing types of Willowglen I/O cards.
"There are Wizards for configuration," says Dion Dubé, manager of measurement project services for Enbridge Pipelines Inc., operators of the world's longest crude oil and liquids pipeline system, who worked with Willowglen on the design of the Unisen line. "Installation really becomes just a matter of sliding out a card and putting another one in. There's no wiring change, no I/O change, no cabinet change."
Unisen's web-based capability is a bonus for Enbridge's far-flung operation. "All our sites are connected through an intranet. We can make all changes, configurations, etc. right from our offices in Edmonton," Dubé adds.
Make it easy to expand an RTU after the initial installation. The Model 2204 RTU supports four I/O cards with a maximum point count of 32. The Model 2208 supports eight I/O cards with a maximum point count of 64. Using expansion racks, users can easily expand the RTU to support more than 2000 I/O points on a single RTU.
Make it easy to connect to third-party devices. Willowglen designed in the ability to talk to many different devices and still retain the ability to add in new protocols. A built-in, four-port Ethernet switch is standard as part of the Unisen line of RTUs, and compatible with 10/100 MBit speeds. Six serial ports are included that support RS-232 and RS-485.
Make it easy to program. The line includes a complete implementation of all five languages in the IEC-61131 standard, including Ladder Logic.
Makes it easy to add redundancy. For customers with critical applications, Unisen RTU can be installed in a redundant configuration, with the two RTUs sharing data.
Make it easy to adapt the RTU for particular applications, including gas and liquid petroleum products measurement and electric industry requirements, such as GPS interface modules, NTP support and sequence-of-events inputs. Willowglen provides full support and hardware and software for these specialty applications.
In addition, one other feature of the Unisen RTU line was "huge" for Enbridge's Dubé—backward compatibility, which makes the economics of upgrades quite attractive.
"Our current RTUs are getting old," explains Dubé. "We needed upgrades that would work with legacy systems."
Enbridge has worked closely with Willowglen throughout the development of the Unison line and has beta-tested the RTUs. Dubé says the company has plans to install them at two sites during this year. "Our experience has been very favorable," he says. "Willowglen does a great job of considering their customers' needs, and they offer great support."
The Unisen line of RTUs is due to be released by the middle of April 2010.