Safety concerns overshadow all aspects of industry, from transportation to plant air quality. Some innovative solutions are discussed below.

Avoiding Casey Jones

Railway companies are looking to replace aging controls with more reliable, intelligent technology "because unlike traditional manufacturing processes, railroad accidents cause more than just downtime and loss of product," explains Dwayne Edwards, general supervisor of signals and structures at Paducah & Louisville (P & L) Railway. The most recent safety initiative at P & L involved auditing and improving the technology used on one of its signaling systems. While the P & L signaling systems haven't been a problem to date, the company chose to focus on them due to their aging control technology. "Some of the control technology used in signaling systems is up to 60 years old," said Edwards. "There comes a point in time when you need to replace this technology even though it is properly functioning."

P & L incorporated Rockwell Automation technology that was certified fail-safe and met the new guidelines set forth in the International Electro-Technical Commission (IEC) 61508 standard for functional safety of electrical, electronic, programmable electronic safety systems. "We calculated that by replacing some of the relays and other mechanical components, we could reduce maintenance of a signaling system by as much as 50%," says Edwards. This proved correct when P & L updated the signaling system on its Rockport drawbridge, spanning 520 feet over Kentucky's Green River.

The backbone of P & L's solution is Rockwell's Allen-Bradley GuardPLC1200. This fail-safe controller is designed to monitor the bridge sequence and all of the interlocks, span locks, and lift rails to ensure the accurate raising and lowering of the drawbridge. On the bridge's signaling system, the GuardPLC monitors four NF proximity sensors and 16 relays. By replacing the switch machine, linking system, and 30 relays with the PLC-based system, P & L is left with far fewer mechanical components to maintain. The company can now eliminate four days of maintenance monthly. (For more, click here.)

Testing the Tests

Averna Technologies upgraded and automated Honeywell's auxiliary power unit (APU) test facility using the National Instruments SCXI and LabVIEW platforms to integrate the necessary signals and measurements. Regulatory agencies require engineers to periodically shop-test all APUs, which are used on most jet engines, military vehicles, rockets, and spacecraft. In a typical test scenario, engineers ignite and power up the APU with different conditions to verify that thrust generation, fuel consumption, vibration, and other operational characteristics are conforming to design. Engineers isolate APUs in a special cell of the test facility away from control equipment and personnel for operational safety.

"For the Honeywell solution, we used LabVIEW code to read standard configuration files and an operator to perform APU-dependent configuration by simply selecting the test unit type from a drop-down menu," notes Averna's Shahzad Sarwar.

Averna used the APIs in the software modules it developed with LabVIEW to maintain full programmatic control of test hardware from other Windows applications. Using this feature, engineers now can perform full test automation with Averna's Proligent process-mapping, collaborative software. "With Proligent, we could run a complete test sequence without needing any operator intervention," Sarwar explains. "On the throughput side, we reduced the test cycle from an average of 12 hours per APU to a mere two hours, generating a productivity gain of 600%." (For more, click here.)

Keeping Smoke Out of Their Eyes

When a leading manufacturer of HVAC filtration products for residential, commercial/industrial, and HEPA applications faced a problem with the air quality in its largest manufacturing facility, it turned to United Air Specialists (UAS) Inc for a solution.

The manufacturing process used to produce these filters creates a thick haze of fiberglass particulate matter in the atmosphere of the plant. Although it posed no serious health threat, it had a large irritant factor, with dust settling on clothes and hair -- and despite the use of safety goggles and glasses, in employees' eyes. In fact, one third-shift employee's full-time job was to sweep up all the dust from the previous day's work.

"It was just a nuisance for employees," said the plant manager. "Nearly every day, someone would require medical attention because of dust in their eye. That's $40 to $50 an incident, plus the lost time. We really wanted to solve this problem." After observing and doing some research, the UAS engineering team recommended the BDC 22T dust collector. The compact, self-cleaning, continuous-duty system uses a pulse-jet cleaning system to effectively "pulse off" captured dust and clean the filter while the system stays online.

UAS also supplied motor starter panels and a separate digital pressure and pulse control panel, which help govern and monitor the self-cleaning system. The gauge on the control panel indicates the dust loading condition of the cartridge filters, while the circuit panel activates continuous pulse cleaning. Users can adjust a switch inside the Pulse Control Panel to activate a downtime-cleaning mode upon system shutdown, as well as program pulse cleaning sequences as required. (For more, click here.)

Treating Sewage Right

Valley Electric Co of Everett, WA was awarded the contract to retrofit the electrical systems in a sewage lift station that is part of a subsystem supporting more than 300,000 people. Its three pumps can move up to 9.2M gallons per day. In the event of a total shutdown, county workers have roughly 40 minutes to bring it back online before sewage spills into the nearby creek.

The company built a duplicate electrical system in a modular structure next to the pump house, and Valley Electric's Brian Glazier developed a testing plan that incorporated key elements of conventional electrical commissioning along with the load testing. They would first check all the connections, then power up each of the four drives and run it for 15 minutes at 30%, 60% and 100% of rated output. At each step they would verify that the drive was indeed putting out what was on its display. The company used a Fluke 1587 insulation multimeter, which combines the functions of a digital multimeter and megohmmeter, to take current readings and make sure the current to the load bank was within tolerance.

Once Valley Electric powered the system, it took measurements at the utility meter to make sure the system was not pulling excessive current and that voltage was close to 277 V. The multimeter handled voltage measurements at every point in this system, from the temporary feed at the utility CT can all the way to the drives. And with a current clamp accessory (a Fluke i400s with adapter), it could measure the current as well. (For more, click here.)