1 June 2007
Wireless networking benefits
Pickle plant plan pays for itself in less than four months
By Dan Bowen and Doug McNeil
Wireless technology is becoming the rage throughout the industry, but questions persist about its reliability, security and its robustness. But with more companies using the technology, manufacturers are becoming more secure in the fact wireless works in an automation environment.
One case in point is Mt. Olive Pickle in Mt. Olive, N.C.
The company is becoming more reliant on electronic data interchange technology all the time. In fact, the company receives more than 90% of orders electronically from retail customers and sends electronic invoices to about 80% of customers. When a new electronic data interchange format called advanced ship notice came on the scene, Mt. Olive knew it had to upgrade its warehouse management system.
Upgrading the warehouse management system required Mt. Olive to implement bar code scanning equipment that could capture inventory and other information and transmit it over the company's network. Additionally, the company needed to upgrade its existing two-way radio communications system. Rather than invest in a new tower and radios, the company elected to use wireless Voice over IP (VoIP), which meant it needed a complete blanket of RF coverage to augment its existing wired Ethernet network. The facility encompasses 600,000 square feet of indoor space and 2 million square feet outdoors, all of which required coverage.
Ultimately, the firm opted to install wireless access points in conjunction with a wireless controller to extend to every possible area of Mt. Olive's manufacturing footprint, including outdoor areas such as its waste water treatment facility and brining tanks.
In addition to helping it achieve the RFID implementation, the new wireless network gave the company the ability to monitor and control equipment located outdoors, on the factory floor and in the warehouse facilities from any computer attached to the network. The move saved the company about $100,000 in maintenance costs over three years and $2 million by reducing downtime in manufacturing production lines. The new system also enabled a paperless work order entry system to save time and money on maintenance overhead. That saved the company $1 million over three years. By integrating an existing VoIP PBX, they were able to replace the costly two-way radios that didn't cover all areas of the facility anyway.
The company was only going to move forward with the new system if it could handle the harsh factory floor, warehouse and outdoor environments. The company was also looking for a simple, but secure system that would support future upgrades, such as a video security system and combined PDA/VoIP devices.
Mt. Olive originally wanted to deploy a decentralized wireless LAN, where each access point (AP) controls its own security and roaming functions. Called "fat" APs, they can stand alone or work as part of a larger pocket of wireless coverage with other APs. While this architecture works well enough for implementations with a small number of APs, it becomes difficult to manage in large networks or with multiple isolated pockets of RF coverage.
The APs Mt. Olive picked enables them to work with controllers from several manufacturers, which then become the "brains" of the wireless network and take over the security and roaming functions of the fat APs. The result is the fat AP becomes a "thin" AP and the central controller handles all management functions, including VPN management, monitoring functionality and real-time RF visualization for IT personnel. The controller is able to understand when a device is moving out of range of one AP and will initiate the hand-off to another AP with a stronger signal. This feature also works with automated guided vehicle (AGV) applications, where fast roaming times are crucial.
As far as security goes, the centralized controllers can detect when a "rogue" AP connects to the network, such as when an employee installs an AP without the knowledge of the IT department. These rogue APs expose the entire network to anyone who can pick up the signal, and potentially interfere with legitimate RF signals. The protocol for this network is to find the rogue APs and shut them down.
One of the other issues behind fat APs is users have to manually manage or maintain them. That would mean a technician would have to climb up in the rafters each time the device needed tuning or any other maintenance. By contrast, users can centrally manage the thin APs. Should one fail entirely, the central controller will automatically bump up the power of surrounding APs to compensate so coverage remains intact. As soon as they replace the failed AP, the central controller automatically downloads the proper configuration and reverts surrounding APs to their normal state. The controller can even e-mail or call an administrator to post an alert about system problems.
A new data view
Mt. Olive Pickle now has wireless coverage where no network connections previously existed. The company is totally wireless, fence to fence. Previously, its Category 5 cable covered roughly half of the square footage of its various buildings, including office and maintenance facilities. Now the wireless network covers all of its buildings and the outdoor areas.
Covering the outdoor area is key because those outdoor facilities include systems that require close monitoring, including the waste water treatment plant and a tank yard where the company stores pickles while brining. With the wireless network, maintenance workers can now monitor all of these systems remotely, receiving alerts in real time when things go wrong. That is invaluable to Mt. Olive.
Just look at the waste water treatment facility. The company invested $6 million in the waste water facility and operates it under a government permit that allows the company to discharge treated water into a nearby stream.
Mt. Olive has to monitor and regulate that discharge very closely. If the company is not within its permit limitation, the government could cite the company for violations, or possibly shut down the plant.
The wireless network now allows for centralized monitoring of the machines along the company's six major production lines, each about as long as a football field. A problem with any one of the machines can cause an entire line to shutdown. Given the amount of pumps, motors, conveyer belts and other moving parts, shutdowns are inevitable. Each month the company averages 25 shutdowns.
As everyone in manufacturing understands, unplanned downtime is unacceptable, so with the quick notification, the wireless network helps Mt. Olive maintenance workers get the lines running again in less time. Using their laptop computers, they can now call up schematics that help them troubleshoot the machines they are working on. Previously, a technician at the scene of an equipment failure would often have to communicate via two-way radio with a colleague who was sitting at a computer elsewhere in the facility. That was less than efficient, especially considering the radio coverage didn't extend to some areas of the facility. Now, technicians who need help can use VoIP telephones to talk to colleagues who may be familiar with the damaged machine or even call equipment manufacturers for support.
A sign from above
As a point, one week after Mt. Olive started using its IP phones, lightning struck the plant and brought down all manufacturing lines. Traditionally, it would take the company 3.5 hours to restart the lines after a complete shut down. With the new system, the team of maintenance workers with laptops and VoIP phones in tow shaved 30 minutes off that time. Since shutdowns cost the company $56,000 per hour, the increased productivity will save the company at least $2 million over three years. If the company performs better than that, it could save as much as $5 million. In addition, the company will save $100,000 in savings over three years that automated monitoring brings by reducing the need for maintenance workers to walk to various areas of the facility to check water levels, monitor pumps and the like.
Maintenance workers also save time with their new paperless work order entry system. Traditionally, all maintenance jobs-from fixing a broken toilet to repairing a $10,000 pump-required paper work order requests. Main-tenance workers key in the requests to the computer system, at which point the maintenance supervisor would pull together the resources to fulfill the request. Once a maintenance person went to fix the problem, sometimes he may need to order parts to fix the problem. Ordering new parts would require more paper forms.
Utilizing the wireless system, these requests will go directly into the computer system via PDAs and maintenance personnel can enter the parts they need while working on the broken device. This cuts down tremendously on the time the paper has to flow through the proper channels. With 70,000 work orders processed each year, if you even consider a 10 minute savings on each order, at the estimated rate of $30 per hour, it translates to $1 million savings over three years.
After Mt. Olive crunched the numbers, the wireless network system paid for itself in less than four months.
In addition to its original use, one potential application is to have equipment monitoring systems talk to each other, computer-to-computer. Any problem in a production line machine naturally affects all other machines on that line. If one machine can communicate to the others that it has a problem, and enable them to slow down or stop accordingly, it can yield significant savings for the company.
When you are on the plant floor, you can't underestimate the value of having a label machine say, 'I've been down for 30 minutes. Go shut down the conveyer going to the pasteurizer now. If you don't shut it down we're going to overcook about $10,000 worth of product.' That's the kind of machine-to-machine synching this system will allow Mt. Olive to do.
The wireless network provides Mt. Olive with the ability to get information into the hands of the right people at the right time to make the right decisions to make the company as profitable as it can be.
About the Authors
Dan Bowen is Mt. Olive's vice president of finance who also oversees the firm's technology initiatives. Doug McNeil is business development manager for industrial networks at Siemens Energy & Automation. His e-mail is douglas.mcneill
Mt. Olive facts
Mt. Olive Pickle's facilities are on 110 acres with approximately 675,000 square feet of production, office, and warehouse space. The company has over 1,200 fiberglass and plastic brine vats, with storage capacity in excess of 40 million pounds of cucumbers.
Each year, the company uses over 130 million pounds of cucumbers and peppers. The company employs 500 people year round and has 19 maintenance people working on three shifts.