How to run a plant when expertise is lost

Perhaps such a realignment of work is the future for control engineers. Instead of working with the actual equipment, tuning loops and diagnosing problems, you will let software do that work while you operate at a higher level–such as approving invoices from vendors.

Keep the Knowledge
When experienced engineers leave the plant, they take valuable knowledge with them, such as the reasons for certain types of loop-tuning parameters, why PLC logic was done a certain way, or why batch sequences are done in a particular order. Therefore, you should make every effort to capture that knowledge before it is sent away. Good documentation right from the git-go helps, of course, but if that&rsquos lacking, you need to create it. To justify the expense of documenting your existing system, you can explain to your senior management that such documentation will reduce the cost of future upgrades.

&ldquoOften the lack of knowledge of existing systems becomes obvious when customers attempt to migrate to newer generation equipment,&rdquo says Robertson. &ldquoThe first and sometimes painful step along this path is to fully document what the customer has. We provide a wide array of services and technology to make the process of untangling the spaghetti code that we occasionally find for the customer so they can migrate their valuable configurations.&rdquo

Givens has known this for years. &ldquoWe configure and build controls, write software, diagnose process problems, tune controls and, occasionally, train technicians,&rdquo he says. &ldquoWe have detailed records of every single bump test done to every single loop since the day we went into business. I can find the data files for every one and tell you how I calculated the tuning parameters, how I determined how much backlash/stiction was present, and so on.&rdquo

A great deal of new software is available to help you document your system. Wonderware&rsquos Industrial Application Server, for example, allows control and system engineers to standardize system implementation and encapsulate knowledge on ArchestrA-based systems, says Steve Lewarne, Wonderware's vice president of product marketing.  &ldquoArchestrA provides a structured model and approach to designing supervisory automation and information systems,&rdquo he explains. &ldquoArchestrA is also self-documenting with respect to initial configuration and modifications made throughout the life cycle of the system. These allow system engineers to easily design, build, deploy, and maintain secure and sustainable automation and information applications.&rdquo

Yokogawa has something similar. &ldquoYokogawa has developed a software solution called Exapilot for capturing this fleeting best-operations knowledge,&rdquo says Fred Woolfrey, Productivity Solutions Consultant at Yokogawa. &ldquoExapilot is a Microsoft Windows-based operation efficiency improvement software package that allows operating personnel to standardize and automate what would normally be manual procedures and incorporate the know-how and skill of expert operators. Operating personnel can build and modify these procedures with an icon based interface. Users can easily configure and test complex procedures. Procedures built with Exapilot can be used to standardize and automate manual procedures, improve plant efficiency, and improve the safety of plant operations.&rdquo

Because vendors must document what they do when developing and configuring control systems so they can support them later, they&rsquove developed such tools for their own use. Check with your control system vendor to see what&rsquos available.

Train and Keep Maintenance
An I/E Supervisor at a power company in Texas trains his technicians and spreads the knowledge around, so he&rsquos not crippled if a key person leaves. He&rsquos also less dependent upon vendors. &ldquoWhen we purchase an upgrade or a new system, we add in cost for training in the price of the equipment,&rdquo he explains. &ldquoIf it is not cost effective to send all the techs, then the ones that do attend the training are required to train the rest of the group. I also rotate areas of responsibilities with the techs to keep them current in the understanding, Troubleshooting and repair of the equipment. This helps these individuals become more of an asset to the company and it makes my life a whole lot easier. You can never train enough.&rdquo

He loves the new open control systems, because it gets him away from proprietary hardware. &ldquoControl system manufacturers used to build and supply every component, but now they buy from third parties to build their systems,&rdquo he says. &ldquoBelieve it or not, this is really a cost savings to the customer. For example, if I lose a hard drive on my engineers console, I run down to Radio Shack and buy one at a quarter of the cost than when you had to buy from a single source.&rdquo

It&rsquos not just economics. He says the vendors have lost some of their expertise in repairing their own equipment. All the vendors responding to my question of how much they support their older equipment said they go back to the dawn of time, but that&rsquos what you would expect them to say. They did not say they had experts doing the work. Therefore, you can probably build a case against letting a vendor take over maintenance on your system on the basis of cost and performance. Cruising the automation lists on the Web would probably get you enough anecdotal evidence to even make a flint-nosed bean counter think twice about outsourcing maintenance. Keeping equipment knowledge in-house helps keep jobs for you and your techs, but you also have to be cost effective.