PINTO’S POINTERS
About 35 years ago, distributed control systems (DCS) replaced large central control-room main-frame computers. In a traditional slow-growth business, DCS was the fastest growing new segment.
DCS was ‘distributed’ only when compared to the complex systems which dominated control rooms at the time. But these were still fairly large clumps of mini-computers, with multiple marshalling racks of wiring to field-based input/output (I/O).
With the arrival of personal computers, ethernet and fieldbus, everything started to get smaller and was networked. Wireless networking was supposed to get rid of the I/O racks. But how could anyone get away from wiring up hundreds and thousands of I/O points?
Emerson’s Delta V was the first small PC-based DCS, introduced in 1996. The new DeltaV S-series, introduced in September 2009, includes major enhancements to all I/O processing, operator displays, asset management, batch capability and system security. But its major achievement is a fundamental, innovative re-think of I/O wiring called ‘I/O on Demand’.
Innovative Electronic Marshalling essentially eliminates the need for a physical path from signal-source to controller. Instead, new single channel CHARacterisation ModuleS (CHARMS – cute name) relay I/O info via the ethernet backbone to any controller, providing single channel integrity and flexibility down to the channel level.
The human-centred design approach, and the resulting ‘I/O on demand’ architecture, is like applying the principles of lean manufacturing to the work processes around an automation project.
On a typical project with 16,000 hardwired points for example, I/O-on-demand alone can cut the number of cabinets by 50 per cent and their footprint by 40 per cent, while eliminating as much as 90 per cent of intra-cabinet wiring. This reduces engineering time dramatically and ensures that changes to the original design can be readily accommodated without rewiring – a big problem with legacy DCS.
Getting rid of wires eliminates most activities associated with wiring design and installation. Cabinets, wire, terminations, cable tray design, fusing, installation drawings and a host of other activities are gone. The S-series incorporates a major enhancement for WirelessHART networks, cutting wireless network design time by about 20 per cent.
By putting usability and productivity at the heart of product design, Emerson meets two vital needs of today’s global environment: skills shortages in emerging markets; and an aging experienced workforce in the developed world.
DeltaV S-Series is no ivory-tower re-think. Emerson insiders tell me that they worked the design every step of the way with a large petrochemical customer. Bravo, Emerson team, for yet another engineering and market coup!
Jim Pinto
jim@jimpinto.com
www.jimpinto.com