A brand-new family of MACO control systems from Barber-Colman Co. in Love's Park, Ill., employs a "building-block" strategy intended to reduce the system's installed cost while improving its performance.
Called MACO DS, this modular control system literally snaps together from three types of new components: process-specific control modules, a quick-connecting distributed I/O system, and a PC-based operator interface. These components communicate via high-speed buses and industry-standard communication networks such as Ethernet and CANBus. "It's a truly open system," says automation products manager Bart Polizotto.
"The focus of this system is on lowering the total installed cost," Polizotto emphasizes. That cost is roughly 25% less than for earlier MACO systems, he estimates.
Barber-Colman previewed MACO DS at the recent K'98 show in Dusseldorf, Germany. While the system will not be fully commercial until July, a prototype was demonstrated on a rotary blow molder from Graham Engineering Corp., York, Pa.
For process control, MACO DS relies on what the company calls "Application Specific Blocks," which contain I/O card modules with on-board microprocessors and also have room for an optional central microprocessor that can run custom control routines. A "block" holds up to six of these intelligent I/O cards, each handling a specific control task. Users simply select the cards that meet their application's needs.
When MACO DS arrives this summer, Barber-Colman will offer off-the-shelf control modules for blow molding, injection, extrusion, temperature, and motion control. Some of these cards contain control features already familiar to Barber-Colman customers--for example, Impact injection molding control. Other cards will be new introductions that will provide performance increases, according to Polizotto. For instance, a high-speed card currently used only in blow-molding will be applied to injection molding. Polizotto says the 0.1-millisec scan rate of this card will permit a more detailed shot profile of 100 steps instead of the current 10.
MACO DS also offers direct wiring of the system's components into one or more "terminal I/O blocks." Each block has a base comprising 25 DC, AC, and analog I/Os.
More than just a place to hook up the wires, the base also supports a snap-on communications adapter, which provides a single-point connection with the application-specific block over a high-speed bus. Polizotto says the chief benefit of the terminal-block system is simplified wiring and the ability to buy only the amount of I/O you need.
The system's new operator station, called Optima PC, features a color touchscreen and an integrated pointing device. Because it runs on Windows NT, the system offers quick integration with a variety of factory networks from Barber-Colman and other suppliers.
Optima uses Wonderware InTouch software for its operator interface. Standard features include multiple windows, on-line help, animated objects, SPC, on-line trending, and recipe management.
To upgrade earlier MACO operator stations for use in a MACO DS system, Barber-Colman offers a small Windows CE device that bolts onto the older system.