Even as it has helped I/O to escape its old constraints, the practice of human-centered design has been used to make important usability enhancements to conventional I/O as well.
In the Emerson DeltaV architecture, HCD is embodied in the new DeltaV S-series I/O cards, which carry forth the electronic functionality of the company's proven M-series I/O, but are re-engineered to deliver a new level of easy, error-proof installation and operational robustness.
"The S-series I/O cards use the same electronics and software that has been proven for more than a decade in the M-series hardware," says Duncan Schleiss, Emerson vice president of platform strategy. "And, by the way, customers can upgrade to the DeltaV version 11 without needing to upgrade to S-series I/O."
Installation Error-Proofed
One HCD-driven improvement is the S-series' patent-pending heat dissipation technology, which features a plastic cover over the top air vents to prevent items from dropping down into the card from above and shorting out the circuitry.
The new cards also offer "easy-on-hard-off" installation, which means there are no screws needed to install a card onto the backplane, yet releasing one requires pushing an out-of-the-way release button on top of the card. Further, S-series I/O cards are automatically "auto-sensed" when added to the system. This helps makes maintenance error-proof, ensuring that any replacement I/O card is of the proper type. A guide prevents bent pins and cards easily snap in place.
System availability is addressed with S-series I/O by allowing the online addition of new components without shutting down. Controllers, I/O cards, field devices and workstations can be added while the host system is powered and running—any system can be upgraded or expanded on-the-fly with no downtime. System uptime is also enhanced through the available redundancy of system components, including controllers, control and field interface power supplies, controller Ethernet communications and many field interface cards.
Modular and Compatible
Importantly, both S-series and M-series I/O hardware can coexist in the same DeltaV system with no trade-offs or incompatibilities. And while it doesn't offer the single-channel modularity of Emerson's new electronic marshalling approach (see story, p 10), the S-series does allow users to specify the exact number of I/O cards, 8-wide carriers, power/controllers and 2-wide carriers needed—and the flexibility to add more I/O as the system grows.
The DeltaV system supports a full range of analog, discrete, digital bus, thermocouple and RTD field devices. DeltaV control hardware is built rugged and flexible to mount almost anywhere and is designed for extreme field installation conditions, including: Class 1/Division 2 areas, CENELEC Zone 2 areas, and ISA-71.04-1985 Airborne Contaminants Class G3.
All DeltaV I/O cards are rated for extreme operating temperature ranges of -40 °C to 70 °C (-40 °F to 158 °F) and can be mounted in field junction boxes, significantly reducing equipment footprint. Shared remote I/O is available for Zone 2 installations. Unlike other remote I/O, DeltaV remote I/O can be shared among several controllers for a greater range of applications and installation flexibility.
