Computerized automatic controllers serve as an aquatic center's onsite eyes, ears and, yes, brains, allowing facility operators to monitor mechanical systems from near and far
Officially, Jeff Groff's title at Franklin & Marshall College is HVAC/R Technician. Unofficially, though, Groff goes by a more laudatory designation: "Superdude" - a nickname that, given the number of building mechanical systems Groff oversees, is apropos.
Groff's duties require him to be in 62 places on the Lancaster, Pa., campus at once. Naturally, this is physically impossible, but with the aid of computerized automatic controllers - such as the one that operates the dehumidification system in the school's new natatorium - Groff can appear to be superhuman, at least in the sense of his ability to "see" through Franklin & Marshall 's brick walls.
Features such as automatic data logging software and online monitoring capabilities make the dehumidification system in the Kunkel Aquatic Center, the centerpiece of which is a 50-meterby-25-yard, 650,000-gallon competition pool, among the most technologically advanced air handling systems available today. "The Internet connection is great," says Groff, whose central campus office is separated from the aquatic center by a 22-court tennis complex, recreation fields and a student parking lot. "It eliminates me having to go in there and check the temperature if somebody on the aquatics staff thinks it's a little warm."
If a more serious situation were to present itself, alarms ranging from minor (low oil pressure) to major (inoperable fans or dampers, or a fire) would be triggered and the system would immediately alert Groff on his pager or cell phone. As helpful as that feature may be, it's trumped by another that allows the system to be repaired by the manufacturer's service technicians via a static Internet Protocol (IP) address. Should an alarm go off, "the system automatically generates an e-mail to them," says Groff. "Sometimes, they catch things before I do. Or if I'm on vacation, I'll come back and everything will be fixed."
Peace of mind is perhaps the greatest selling point of the mechanical systems available to operators of today's sports and recreation facilities - from pools to ice rinks (see "Cold Case," left). The plethora of gizmos built into pool chemical controllers and environmental control systems are certain to dazzle even the tech-savviest individuals. Yet the collective aim of such devices is not to amaze facility owners but rather to assure them that their daily operations will be free of incident. After all, in terms of mechanical systems, an uneventful day is a good day.
But can facility operators really trust their automatic mechanical systems to hold down the fort in their absence? That depends on several things, including a system's user-friendliness. If the system has online monitoring capabilities, prospective users should find out if its software is compatible with Windows- or Macintosh-based computers, or both. Some automatic systems only require a computer to be equipped with a web browser, Microsoft Internet Explorer or Netscape Navigator, in which case the system can be monitored from a facility operator's home computer or wireless laptop. Next, computers used for monitoring need to have a processor fast enough and a memory large enough to accommodate the system's software program.
Facility operators will also want to make sure their mechanical system's microprocessor controls are easy to program and understand. Or as a president of one pool chemical controller manufacturer suggests, operating the controls should feel "like playing a game on your computer."
Finally, consider the equipment's maintenance needs. A number of mechanical systems for pools are marketed as low maintenance, and some even feature control panels or sensors that can be easily removed for diagnostic exams, repairs or replacement.
Manufacturer technical assistance is available for many mechanical systems, but facility operators should be aware that, as is the case with most building systems, the bulk of routine maintenance tasks will be their responsibility. Periodically, sensors need to be cleaned and calibrated, and gears need to be oiled. "The equipment's pretty reliable," says Groff of his dehumidification system. "But I still have to go in there once a month to check the belts and oil the gaskets."
Some automatic chemical controllers use multiprobes capable of simultaneously monitoring a pool's pH, temperature, total dissolved solids (TDS) and oxidation-reduction potential (ORP), which measure in millivolts (mV) the sanitizing potential of an oxidizer in the water. To simplify the cleaning and calibrating process for facility operators, manufacturers of these sensors provide precalibrating pH and ORP solutions (the solutions are preset at neutral-state levels of 7.5 pH and 700 mV, respectively).
In Littleton, Colo.'s Foothills Park & Recreation District, four of six aquatic facilities rely on automatic controllers. Those facilities' ORP sensors are cleaned and calibrated quarterly. Meanwhile, pH sensors might show fluctuations within one week, and therefore are checked more frequently. "We do that just to make sure a probe hasn't gone bad. We don't really mess with it unless the pH is off somewhere within the range of 0.1 to 0.2," says Derek Eberhardt, Foothills' recreation supervisor of aquatics. "We take some kitchen cleanser, scrub the probe with a toothbrush, rinse it thoroughly with water and then dip it in acid." Eberhardt adds that after cleaning, several hours must pass before the sensors return to their neutral state and can be relied upon to accurately record data.
Eberhardt is required by Colorado health codes to manually check water chemistry levels three times daily and maintain backup data logs at all pools. Although he puts a certain measure of trust in the reliability of his sensor data, it's likely Eberhardt would take his own measurements to ensure the accuracy of his equipment's readings even without that mandate. "Automation is only as good as the information my sensors are giving me," says Eberhardt.
So far, however, the controllers' data logs have proven valuable, allowing Eberhardt to track trends in his pools' water chemistry. "Say something changes while someone is on vacation," he says. "I can go back in time and look in the logs to see exactly when that change happened."
Some dehumidifier controllers, too, are self-monitoring (like the system at Franklin & Marshall, for example), and feature software that automatically maintains logs that can be accessed on the Internet at any time - even months later - by facility operators, the manufacturer and/or authorized service technicians.
Another feature offered by some automatic environmental controllers is the ability to control multiple installations via a local access network (LAN) - especially important if an individual is charged with monitoring more than one aquatic facility.
Environmental controls can also be tied into building automation systems commonly used on college campuses. (Because such systems are used to control multiple buildings automatically from a central location, they aren't ideal for, say, a solitary fitness or recreation center.) These systems use communication protocols such as BACnet, LonTalk ® and MODbus ® to operate a variety of components, including door locks and light switches, as well as sprinkler and security systems. (Oftentimes, security precautions such as firewalls are implemented to prevent outsiders from hacking into any operational system connected to a campus Intranet.)
Environmental controllers that are BACnet-, LonTalk- or MODbus-ready can be connected to a campus's existing building automation system, much like one would plug a new printer into an office network. "Before, it was virtually impossible for maintenance personnel to 'talk' to systems in an aquatic facility. It was like its own island," says a vice president of one manufacturer of pool dehumidification systems. "The software allows for a seamless interface with the rest of campus operations."
Not only can environmental control systems communicate like humans, they can "think" like them, too. Some microprocessors - in essence, the brains of environmental control systems - function on what computer experts call "fuzzy logic," a powerful problem-solving methodology that recognizes more advanced data than simple true-false values. Unlike classical logic, which requires a deep understanding of a system, exact equations and precise numeric values, fuzzy logic understands propositions in degrees of truthfulness and falsehood, basing these inferences on knowledge and experience. As a result, information is processed in a manner more closely resembling human decision-making.
Used in a variety of commercial artificial intelligence applications, including programmable washing machines, word processors and high-speed trains, microprocessors that use fuzzy logic are able to make conclusions based on vague, imprecise concepts such as "very hot," "bright red" and "a long time." Take, for example, the statement, "Today is sunny," which might be 100 percent true if there are no clouds, 80 percent true if the sky is partly cloudy, 50 percent true if it's hazy and 0 percent true if it's rainy. Instead of closing entirely based simply on the fact that the sun is shining, a mechanical shade operating on fuzzy logic would analyze how much sun is shining before responding. If it found conditions to be 50 percent sunny over a period of time, the shade would close only partially.
Similarly, fuzzy logic-based microprocessors in environmental controllers can make subjective assessments of existing natatorium conditions and adjust accordingly. "It can tell if the temperature's changing, how fast it's changing and in what direction it's changing," says the pool dehumidification system manufacturer's rep. "Say it's getting hotter. If the outside air is being used for cooling, and it's 50 degrees outside, the controller is not going to open the dampers all the way. It will open them a little bit at first to see if that works. But if things are moving the wrong way really fast, it'll bring all the equipment online much quicker. Fuzzy logic is much more efficient. It keeps the system from overshooting needs."
For the Foothills Park & Recreation District, waste reduction has been the greatest benefit to result from that agency's use of automatic pool chemical controllers. "The difference between automation and manual chemical feeding is that we don't get the peaks and valleys of trying to maintain residual chlorine. We don't get wide pH shifts," says Eberhardt. "From an efficiency standpoint, our chemical usage is way down."
Though they can handle many tasks efficiently and save facilities labor, energy and materials costs, automated mechanical systems can't entirely replace their human operators - nor should they. No system, no matter how advanced the design of its microprocessor, can account for every circumstance. "If we anticipate a busy day or we know an event is coming up, we'll manually increase our ozone production," says Eberhardt, adding that it takes several hours for ozone generators to produce the required amount of ozone to sanitize a pool during times of maximum bather capacity. "It's not the controller that says, 'Oh no, 500 kids are coming in today for swim lessons.' "
There's much to be said for the human element. Humans like things to be made easier for them - thus, the aquatic industry's shift toward automation. But humans also enjoy their personal time, and for their work to stay at the workplace. Eberhardt, for example, cast his vote against purchasing an automated chemical controller with the capability to notify facility operators of alarms via pagers or cell phones. "Then you're basically on call 24 hours a day," he says.
Perhaps Eberhardt fears experiencing what Groff has recently at Franklin & Marshall. The dehumidification system in the school's Kunkel Aquatics Center has a glitch that causes the alarm to occasionally trigger without a valid reason. "There are some bugs, but the manufacturer's technicians are working on it, going back into the logs to see why this thing alarms when it does," says Groff. "Other than that, the system's been fantastic."