We do not want to go back to the days when limit switches with extended trip wires provided the control for our car washes. Those were days of true manual control. We all enjoy the benefits of precise, efficient timing and automation. But how much further could we go if we take the next step and break away from the traditional central control system?


Remember the Cartrol Controller? Some of these may still be in service. They are an early example of automation control in car wash conveyorized tunnels. Cartrol controllers were installed to control special services like waxes and polishes, and there needed to be a way to make timing adjustments. A combination of thumbwheels and dipswitches were used to configure the output device. These were the early examples of HMI (human machine interface), sometimes called MMI (man machine interface).

As technology progressed and became more affordable, early versions of PLCs (programmable logic controllers) made their appearance in the car wash. These devices required a program to be written on a PC, then loaded into the PLC with some sort of interface device like a tape drive or EPROM card. For their time, they were very functional and their use allowed car wash operators to begin to bring automation and efficiency into their facilities. Still, the PLCs of that time required a PC and a certain skill level to maintain and operate.


Configuring a monitor to communicate with the PLC brought more options for control to the operator. Then touch screens became affordable. Better, but it still required the operator to return to, and maintain, a central location to interface with the control system.

There was still more progress with systems coming online (insert phone modem squeal here) allowing for a sense of remote control. Operators could connect with their PC or laptop from a remote location to monitor and adjust in real time. But, we still had to return to a location where we could plug into a phone jack.


With the Internet and WiFi we have a whole new world available to us. We can use our smartphones, iPads, tablets, and other smart devices to connect to the car wash control system. Using browser-based graphical interfaces (HTML5), it is no longer necessary to have a proprietary device.

Web pages are imbedded in the device. No additional computer or server is needed to call up pages perfectly formatted for your device.

Multiple connecting devices can be used at one time. With proper programming, control systems can be accessed and monitored locally and off site by many devices at the same time.

Login requirements and restrictions are available to provide safety and security. Access levels and groups can arrange the wash staff in such a way to allow full access to some, restricted access to others.

Full monitoring and alarming capabilities are at operators’ finger tips. Interactive systems are designed that come and “tap you on the shoulder” when a problem occurs, or even before it occurs. Interactive capability allows the service person to receive the notice or alarm that a problem exists or potentially exists, accepts their acknowledgement of the alarm, and provides instructional material and lists of parts and tools needed to complete the repair. Their work can be logged and recorded to a database for further assessment. There is even GPS stamping available to confirm the work was completed at the site, and not while sitting at McDonald’s drinking coffee!

Use off-the-shelf interface devices and save money. Using everyday smartphones, iPads, or Android tablets — basically any device that supports a browser — saves huge dollars when compared against the cost of typical HMI touch screens and traditional PCs and monitors. Obviously, things happen. So when the iPad gets dropped into the conveyor pit, all that is needed to replace it is a quick trip to the electronics store or an overnight order from Amazon. Proprietary software is not needed because the interfaces are browser based. The only configuration necessary when devices are added or replaced is to connect to the appropriate WiFi network.

No need to be tied to a central location. Take the interface device with you as you build, maintain, adjust, and support the car wash machine.


Another control system technology available to installers and operators is the concept of distributed I/O (input/output devices). The concept is similar to what we discussed regarding interface devices — move away from the idea of a central control panel and spread out the system by putting I/O control devices where the application or motor actually is installed.

Distributed I/O, sometimes called remote I/O, will have a higher initial purchase cost. Our experience, however, has verified that the additional upfront costs will be paid back two or three times over in saved electrical installations costs. Reduced conduit and wire runs, time and labor costs, in addition to less clutter can be achieved with simple, smaller control panels connected by an Ethernet network. Decentralizing the electrical control and power system will aid installation and reduce costs using off-the-shelf materials.


Several things need to be considered when designing a control system with these concepts. With technological advances in electrical power and control equipment, skilled electricians and installers are a must. Hire electricians with the experience and skill set to both install equipment and provide service later to keep you running and washing cars.

Using the least expensive installers and electricians may work out in the short run but almost never works out in the long run. Lack of experience and skill means underbidding the job, cost over-runs, and expensive change orders. The inability to provide your facility the service and support you will need in the future to maintain your car wash equipment will prove costly.


Lastly, consider your ISP, WiFi, and Ethernet networks as essential parts of your car wash equipment. Just as it is essential to have a plumber, welder, and electrician in your “back pocket” for critical service needs, you will need a skilled network expert who is available and knowledgeable for service of your system.

Scott Fausneaucht has 32 years’ experience in car wash control systems and is with Guardian Control Systems, a division of Tommy Car Wash Systems. You can visit the company on the web at www.tommycarwash.com.