By Mike Bacidore, managing editor
Choosing between an industrial component and an off-the-shelf, commercial substitute can be intimidating, if you haven’t done your homework. An unnecessarily rugged industrial component could translate to a sizable amount of money wasted on excessive precaution. On the other hand, an inappropriately implemented commercial component could mean destroyed equipment, lost production time or even injured employees.
Knowing how to make the right decision comes with experience, but how many engineers come ready-made with that type of veteran savvy?
Practical wisdom included. Just add water.
Typically commercial components are more readily available and less expensive than their industrial counterparts, but their reliability can be suspect, especially in harsh environments where conditions, such as temperature or vibration, can be extreme. And some applications are more suited to one type of component than the other. But no hard and fast rules exist, and exceptions always arise.
“Even though coal mines and plants are harsh environments, a lot of times we’ll use commercial components,” says Bruce Bancroft, consulting analyst at Consol Energy (consolenergy.com), an underground coal-mining company headquartered in Pittsburgh. Bancroft heads a group that oversees applied improvements in Consol Energy’s engineering and coal departments. “I’ve had nothing but hassles with industrial PCs. I’d rather buy a commercial PC and put it in an enclosure. Industrial PCs have never lived up to their expectations. It hasn’t been worth it for the cost.”
With 17 complexes in the United States, Consol Energy needs to ensure the data communications between its underground mines and the above-ground preparation plants are in working order.
“We have fiber backbones running throughout our mines, and then we usually come into a patch box and a switch,” explains Bancroft. “We use a lot of standard Cat 5 cable and fiberoptic cable through a relay. We use more commercial-related type connectors for fiber. Any cable in Pennsylvania has to be stamped for flame-retardant capabilities, and we do pay attention to that.”
Because of shorter commercial component lifespans, industrial components often are chosen for their durability and longer expected useful life. However, at some point those industrial components may need to be replaced and sometimes that same product is no longer available. Guarding against the quandary of obsolescence is a simple task if the right steps are taken.
“The most important thing to look at is the history of the company you’re dealing with,” explains Barry Garrison, marketing director at Sealevel Systems (sealevel.com), Liberty, S.C. “You have to look at the company level, not the product level, and how they handle their program. How risky are commercial substitutions in these instances? It comes back to the nature of the application and the environment. If you start factoring in how important the application is, then you’re running a big risk [with commercial components].”
Companies can guard against potential obsolescence by examining the products and the philosophy of the company with which they plan to do business.
“Knowledgeable designers guard against obsolescence by examining the track record of their candidate suppliers,” says Peter Wood, vice president of engineering and operations at GarrettCom (garrettcom.com) in Fremont, Calif. “Typically low-cost commercial components are not properly designed and tested for longevity in harsh industrial environments. Adequate design and testing cost more and account for the higher industrial component cost.”
The expected lifespan of the equipment is important too. In Orange County, Fla., like every other county in the U.S., waste and wastewater utilities are ongoing public necessities.
“Obsolescence is a big problem as we often look at 10-to-15-year installations before they are overhauled,” says Joe Roegner, SCADA technician for Orange County (orangecountyfl.net) in Orlando, Fla. “After only a few years we get equipment that can’t be repaired. Due to the fast advance of technology you have to consider that in five years what you have could be replaced with even better equipment.”
Sometimes, an industrial component will provide the user with a longer window of time for both product availability and the eventual replacement of legacy parts, suggests Greg Dixson, marketing manager, automation systems, at Phoenix Contact (phoenixcon.com) in Middletown, Pa. “Commercial products exist in and are developed for a market that typically cares about price first, with product durability and support as a much lesser concern. In the industrial market, price pressure often is tempered by a non-negotiable demand for product reliability. As a result, well-designed and ruggedized products, even if their cost of manufacture is not the absolute best in the market, will remain competitive, and therefore in market demand, for a longer period of time,” he explains.
Dixson also notes that the customers of most industrial component manufacturers simply will not tolerate a vendor quickly making a product obsolete that has been tested and designed into an application (Figure 1). “Such a practice results in a customer incurring the costs associated with approving and specifying a new product,” he says. “Since most industrial manufacturers have many different products to sell to a customer, they will often extend legacy support of an older generation product for a great deal of time in order to keep their larger customers happy.”