Though it was past closing time at the company’s Shelbyville, Tenn., car wash, an employee had failed to close the rear door on the facility. With just a few mouse clicks and keystrokes on his laptop, Gammon was able to close the door and secure the facility some 1,800 miles away.It’s an example of just one of the things that Gammon can do remotely from his laptop, thanks to a new Web-enabled control and automation system that Nashville-based National Car Wash has installed on several of its car washes. The system, known as the Tunnel Commander, is controlled by a Modicon Premium TSX 57 programmable logic controller (PLC) supplied by Schneider Electric, a French company with U.S. headquarters in Palatine, Ill.Keeping tabsThe system includes a touch screen control panel for use by the operator at each car wash. But when the operator is away from the panel, or if problems arise that the operator can’t handle, Gammon is able to intervene remotely as needed. Using Schneider’s Transparent Ready feature, which enables remote monitoring and control over the Internet using a standard Web browser, he is able to keep tabs on each of the company’s Tunnel Commander-equipped facilities. “When a car goes through a wash, I’ll actually see a graphic of a car going through, and all the brushes and components turning on, representing the outputs and inputs of the PLC,” says Gammon. “So I know exactly what’s going on at the car wash. If there’s an error, it alerts me with an e-mail, and it will also send a message to my phone.”Say, for example, that sensors detect that a vehicle at the end of a tunnel has not been driven out, and is stopped within the exit of a car wash. This triggers an “anti-collision mode,” automatically stopping the car wash conveyor system pulling other cars through, while displaying a message on the control panel to check and clear the exit. If the operator is dealing with a customer, emptying trash, or otherwise not monitoring the control panel, however, he or she may not notice the stoppage. But because the system also alerts Gammon via e-mail and a call to his cell phone, Gammon can quickly call the operator—who carries a phone at all times—to alert him or her of the problem. This capability is particularly important, given the fact that the automated features of the Tunnel Commander system have enabled National Car Wash to cut back on the number of employees on duty at each car wash site—from three or four workers previously to just a single operator today, Gammon says. It has also eliminated the need to have a “talented individual who knows the system” on duty at all times at each car wash, he adds. “All of the information comes to me, and it allows me to be that talented person, because it allows me to be connected to the car washes at all times.” For National Car Wash, the benefits of using the Tunnel Commander system are several. One of the biggest advantages is a savings of about $60,000 per year in salaries per car wash, thanks to the need for fewer workers, Gammon says. Other benefits include a 33 percent savings in energy costs, due in part to more precise and efficient motor control provided by the VFDs. The single-cable requirement for the CANopen connection also significantly reduced installation costs, when compared to more complex wiring schemes required by previous approaches. In all, according to Gammon, the savings provide National Car Wash with a return on investment of about six months for each Tunnel Commander system installed. Planning for moreOf some 50 car washes in the National Car Wash system, which includes Tennessee, Western Kentucky and Michigan, only three currently are tunnel washes—all three of which have been equipped with the Tunnel Commander system. The other washes include both self-service bays, and “roll-overs,” in which the washing apparatus moves over the car, which remains stationary. Gammon says the company has plans over the next few years to convert all of its car washes to tunnel washes equipped with the Tunnel Commander. Further, the Tunnel Commander will be mandatory for all tunnel washes opened by franchisees in the future. “That’s going to be one of the requirements when we build the system,” Gammon explains, “so that we can remotely monitor their car washes to make sure that they’re working as efficiently as our franchise agreement requires.”
Additional Schneider components include eight Telemecanique Altivar variable frequency drives (VFDs) for motors that operate car wash dryers, blower panels and water pressure controls, as well as a motor control center equipped with a Telemecanique Advantys distributed input/output (I/O) system that connects to the PLC via a CANopen (for Controller Area Network) link. Various sensors are used to detect vehicle presence, soap solution tank levels, hydraulic system fluid levels and other parameters, and the system can automatically make adjustments or alert the operator when action is needed.
For more information search keywords “Web-based monitoring,” “Web-based control” and “Transparent Ready” at www.automationworld.com.
