Maintenance Management: Audit of key data is essential for electrical equipment
As industrial plants adapt and expand, it is all too common to find electrical equipment that is unfixable because key information is not available. With internal configurations, codes and passwords o...
June 1, 2002 | By Judy and David Van Rhijn
As industrial plants adapt and expand, it is all too common to find electrical equipment that is unfixable because key information is not available. With internal configurations, codes and passwords on even the simplest controllers, maintenance staff can find themselves stymied by a lack of documentation. A plant-wide electrical audit is the answer.
Manufacturing plants often house a collection of electrical equipment from many different sources, and in the ever-changing world of computer technology, from different eras. A PLC program may require a password and special software for loading a program. A drive may require a certain parameter to be entered before you can make modifications. Even plants without PLCs have the potential to have devices that require configuration.
There are many reasons why backups and other documentation may not be not available — from “never collected,” to “lost” or “completely out-of-date.” When Diamantino Silva came to work at Colonial Cookies of Kitchener, Ont., as an electrician, there was a noticeable absence of electrical information. He organized a plant-wide audit on everything from programmable limit switches to panel views. “The company’s philosophy is mechanical,” he explains. “It was the first time they had tried looking for electrical problems.”
When Kitchener, Ont., based Humpty Dumpty was taken over by Small Fry Snack Foods in 1995, a great deal of information was not passed on at its plant in Mississauga, Ont. At the time, the new maintenance manager, George Strickland, faced the formidable task of gathering PLC programs, drawings, variable frequency drive parameters and operator interface programs, among other information.
“There were a lot of things that we needed to understand,” he says. “The previous maintenance manager took a lot of the knowledge with him, and then two key technical people left. There was not a lot of cross-training, so we had to call people in.”
In an ongoing operation, new installations are frequently the cause of difficulties. Maintenance is not always put in charge of new equipment immediately, and it may be some time before anyone realizes the inadequacy of the information. If corporate staff has not put agreements in place to get the information from manufacturers and contractors, the maintenance staff may be left in a hopeless situation.
Strickland points out that he can often buy parts and equipment locally, but needs the installer to tell him how to configure it. “It’s a Catch 22 situation. They can be very reluctant to share.”
Another problem occurs when designs change during a project but documentation for the original designs are provided, or when equipment is customized but the documents are standard. If you later replace the equipment and don’t know to make the changes, it can cripple production for no apparent reason.
The Weston Foods plant in Kitchener also faced a complexity of issues when it installed its bread line 14 years ago. The expansion was organized on a piecemeal basis over the course of two years. Major electrical work was done on the fly — taking out and replacing machines one at a time on the weekends, so the plant could run for the following week.
“We suffered for two years while it was being done and another two years afterwards because things went that way,” laments maintenance supervisor Stan Brezynski. “The flour panel, the batching system, the bread proofer and the bread wrapper were all programmed by separate firms. They were expected to interface and come back to us with proper documentation. It took four years to get all the information into one laptop and to set up preventive maintenance.”
Problems with new installations can be even worse when you are dealing with original equipment manufacturers (OEMs). They tend to hold back configurations to ensure ongoing repair work comes to them. They also prefer that new equipment is purchased pre-programmed, rather than assisting a customer to download the current programs onto the new equipment. If the OEM is completely unforthcoming, the auditor may have to go directly to the supplier of the components. “There’s a back door for everything,” Brezynski says. “There has to be.”
When dealing with OEMs, Ron Edwards makes the delivery of programs and passwords a part of his purchase order requirements. He is the supervisor of maintenance and engineering at a major London, Ont., firm. “Most OEMs will drag their feet, but they have to provide it because they can’t get final payment until delivery.”
Silva at Colonial Cookies is currently in an unenviable position. The program for controlling some new equipment is in place, but the OEM has password-protected it. Maintenance cannot even go on-line. Getting the password is a matter of politics for upper management, confounded by the fact that the OEM is subcontracted to the hardware supplier, not to his company.
Passwords can present a problem in other situations too. A past employee may have written a program and taken the password with him when he departed. The program will be useless as soon as a change is needed.
Drawings should be included in the audit if the budget allows. How often has a machine stopped and no one knows why? A simple wiring connection may have been altered during repair work and never recorded, meaning a lengthy exercise in wire-pulling is in the cards.
A full set of drawings is one thing Weston’s Kitchener plant can’t provide. “This is not a new plant. There have been 50 years of changes and upgrades,” says Brezynski. “We would have to have a technical support division to keep up with that end of it.” He is all too aware of the disadvantages. “If we had the drawings, we wouldn’t have to go through the debugging stage. That sometimes takes up to six months after a change. Documentation is very important.”
Time needed for an audit
The time that the audit itself requires depends on whether you have one PLC or a whole plant of equipment. It always takes time to get communications to work. Software quickly becomes incompatible with hardware, and vice-versa. For example, the Weston plant in St. John’s, Nfld., recently became a victim of technological advances. “We had the information, but it’s not something you use often, maybe once every 10 years,” says maintenance manager Jack Hickey. “The problem was getting into it.”
Hickey found himself unable to download the information he needed to the company’s newer laptops. “The computer was as old as a dinosaur,” he says of the IBM with a 5 1/4-in. floppy disk drive. Flying a systems analyst in from the mainland was the costly answer. Hickey made sure that a full plant audit was done while he was there and the information securely recorded in a readable form with backups.
Once a plant-wide audit is complete, it is important to update it regularly. Ron Edwards outlines what is needed. “You really should have a checklist designating the individual responsible for updates and someone to verify that the individual is doing what he should do.
“On the list should be the program itself, the software to reload it, the training that allows backups to be done in the event of a major breakdown, how often it is updated and how securely it is kept. The aim is to have the most recent backups immediately available.”
Edwards recommends that backups and documentation be updated every time a change is made, and every year as well. Strickland also favours an annual update.
Brezynski at Weston Foods in Kitchener is even more scrupulous about catching little changes. “You find that somebody else on some other shift called (someone) to change a little thing, so every six months we back up the programs. If we didn’t we would have a real can of worms.”
Brezynski keeps a Program Change Book in the technicians’ room, but compliance is a problem. “It falls by the wayside sometimes,” he says. “It is very difficult to implement something new in-house. Outside contractors are easier to train. They go to different facilities all the time and are programmed to comply with plant policies and procedures. In-house workers are too comfortable with
their routine. It takes about three months before a person will faithfully record every change. We wrestle with that a lot.”
The need for training
Edwards emphasizes the often-neglected area of training. “Don’t underestimate it,” he says. “You need to reinforce training and practice every two or three months. Otherwise you’ll find yourself in the middle of the night lacking software, hardware or the knowledge to use it.”
Security is also an issue that many plants overlook. While they are careful to keep backups of bookwork in a vault, they are less scrupulous with software that is operating the plant day-by-day.
Several copies of the software should be kept in a number of secure locations. It is unwise to replace a old copy that may be needed for reference later. An outdated diskette should be marked with the number of the next diskette and kept. These old disks must be checked for readability or you could find yourself holding an unreadable disk.
Brezynski has a copy of Weston’s programs on his laptop that he updates every 18 months. A technician keeps another, while yet another copy is for general use. “There is a complete set of instructions in there. We tell the workers, if something goes wrong, try and do something. You might get lucky.” He also makes sure that regular outside contractors have a full set of programs. “Then we have the resources to draw from if we need backup.”
Edwards in London keeps two copies — a master book and a duplicate — in a central location. He likes the idea of a third-party keeping and maintaining the backups. “Ideally it should be kept off-site. Stealing and fires are major concerns in the electrical area.” Employee sabotage or carelessness are other possibilities to keep in mind.
Some plants come to grief when they engage OEMs to keep the backups for them. Often an individual is responsible for archiving your particular configuration, and it isn’t always done correctly. It also leaves the plant vulnerable if the OEM goes bust, is bought out or the employee at that firm takes on another job. Documentation standards are a key issue.
An electrical audit can be done by an experienced systems integrator. As well as providing official backups, the integrator should ensure that there are drawings in the panels and revision notes on each machine’s file.
With a systematic plant-wide approach, the maintenance department will have the knowledge it needs to make repairs in the quickest and most efficient way.
Judy van Rhijn is an Australian-trained solicitor and freelance writer. David van Rhijn is a systems integrator and proprietor of SD Control Systems. Both are based in Kitchener, Ont.