Controls are turning into commodities, according to some industry experts. The key difference is in how control intelligence is tuned to specific end user needs. As Geoff Walker, director of automation and drives at Schneider Electric, puts it: "We're not just selling individual products as much any more. We will still sell a contactor to a customer, but we're looking for the all-in-one panel approach." Open systems and data sharing are a must. "Ethernet and TCP/IP is the way to go," Walker says.

Updating the Panama Canal

Examples of this trend abound. Over the last six years Bosch Rexroth has replaced the mechanical drives of the Panama Canal's miter gates with hydraulic drive systems, as part of a $700 million overhaul.

In addition to the widening of Gaillard Cut and an increase in the towboat fleet, the modernization effort sought to bring the lock system's mechanical elements, which dated back to the early 1900s, into the 21st century to meet a projected 20% increase in traffic.

One condition for replacement of the old mechanical drives was that the new hydraulic cylinder assemblies conformed to the original mounting pads on the miter gates and construction footprint on the concrete floor. Each drive system includes custom units using Rexroth AA4VSO pumps, custom manifolds, stainless steel tanks, piping, and safety and instrumentation solutions, as well as customized hydraulic cylinders with base mounting attachments. The company also has supplied the associated central control systems, data acquisition, and data logging for all lock operating machinery.

"The PLC-based control system communicates via fiber optic technology with a backup Ethernet link," says Bosch Rexroth systems engineer Louis Prieto. "It's all part of the central data system." The technology has "generally reduced the maintenance requirements, inventory stock, and operations downtime," adds Carlos G. Patterson, Panama Canal Locks Div project engineer program coordinator. (For more, click here.)

Controlling Air

Industrial air compressor manufacturer Curtis-Toledo Inc turned to ABB when it wanted to upgrade its screw compressors to provide and control airflow supplies in direct response and proportion to real-time operating (load) conditions. The control package included combining its ACS800 drive, built into the compressor, with customized software that controls the system pressure, air delivery, oil temperature, and duty cycle directly from the drive. This approach uses the drive to control the speed of the motor, with its processing power and extensive I/O acting like a PLC.

The control system also provides lead/lag control automatically with two machines: when one machine can't keep up with demand, it brings on the secondary machine automatically. The secondary machine is taken offline when not needed, eliminating the need for any external device.

"This whole application is about saving energy, so having a touchscreen that displays the calculated energy savings as the machine is running is the biggest benefit, followed by its ability to monitor the working conditions of the compressor," says Jerry Elson, national sales manager at Curtis-Toledo. End users can expect annual energy cost savings with ROI in 12-18 months on the drive, and savings up to and possibly exceeding 50%, depending on the air demands of the facility. (For more, click here.)

Semiconductors Uninterrupted

Modernization in the compound semiconductor market means the fine-tuning of scribing and breaking semiconductor wafers. Scribing and breaking are based on principles similar to the art of glass cutting. Loomis Industries chose Galil motion and I/O components as the core of their new LSD-150 scribe and break system. The products employed an Ethernet interface, and Loomis Industries turned to Contemporary Controls for those components.

"A switch was preferred over a hub," says Loomis production manager Jim Cook. "Our programmers said that a switch is more efficient in this application." Since the Galil hardware was not designed to be daisy-chained, an Ethernet switch was required to link up the Ethernet devices that occupied the limited space in the LSD-150 chassis.

Contemporary Controls' BAS switch did not use a power transformer that had a proprietary plug on the switch housing, and Loomis already had a 24 Vdc switching power supply inside their LSD-150 machine. With this Ethernet switch we were able to use up to 36 Vdc, with simple screw plugs to easily connect power from our switching power supply," Cook notes. Once Loomis Industries had connected their Galil-based system via Ethernet, the company's machine was able to do complete production runs without any interruptions. "Ethernet is a time-tested technology that has great capability for problem diagnosis and resolution," Cook says. (For more, click here.)

Pumped Up

For the last three years, Pulsafeeder has relied on AC Tech's variable frequency drives to control the speed of motors in their metering pumps.

"We use their single-phase, variable speed drives both as an off-the-shelf product as well as a custom version," says director of engineering Steve Muscarella. The drives vary the speed of a motor by at least 3:1 turndown. With Pulsafeeder's custom software, the drive turns the motor on and off, yielding pump flow turndown up to 1000:1.

"The value to the customer is that our controller, equipped with the AC Tech drive, speaks pump language, provides steep turndown, and includes a handheld interface panel, which can be mounted up to 1000 ft away from the drive and pump," according to Pulsafeeder vp of business development Nick Valente.

Pulsafeeder and AC Tech engineers came up with a way of bypassing language barriers. "We just needed to make the process totally language-proof," explains Pulsafeeder chief electrical engineer Leo Buchman. "We paint the 'master' EPM a certain color, and each key-colored EPM is added to the manufacturing bill of material. The best part is, if the service team needs to troubleshoot a particular pump, the color of the EPM clearly tells what the drive parameters should be, no words needed." Parameters can be copied in less than two seconds. (For more, click here.)