The answer to this question appears at the end of this newsletter.

Stop Helping Us, Please
Nonessential personnel may not only slow down a repair operation, but they can also introduce repair errors and complicate safety. For example, a corporation with 12 plants had its headquarters at the site of one plant. Any time production stopped, vast clouds of managers would swarm out of the offices and descend like flies onto the production floor, where they buzzed around the repair techs. The wall of bodies made it difficult for the techs to work, as did the constant chatter, questions, and "advice." This extended downtime significantly.

You may not have interference to this degree -- maybe you just have "tolerable" interference from well-intended but unnecessary personnel who pretty much stay out of the way. Nevertheless, this still slows you down, and it still complicates safety.

The solution is to rope off the area and enforce the restricted access. In addition to making it easier for repair techs to work, this prevents exposure of unneeded personnel to the dangers inherent in a repair situation.

Facilitate Fuses
Nobody likes waiting for an out-of-stock fuse while critical equipment is down. An obvious solution is to have all critical fuses in stock. However, that leaves you with the problem of having to spend downtime finding each fuse in the stockroom. The solution to this problem is to maintain a complete set of clearly marked replacement fuses at the protected equipment.

For example, inside the control cabinet for Line 4 is a box that contains all of the power and control fuses for Line 4. However, this solution also presents a potential problem: The risk of, "I'll just stick this in and see what happens."

The solution is twofold. First, ensure the operations group has a "no-operator-touches-a-fuse" policy. Second, write procedures for replacing fuses in specific equipment. Include a listing of the relevant drawings, NFPA 70E information, pre-replacement tests, and how to perform shutdown/startup. The procedures should be in your CMMS and available on demand.

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NEC in the Facility
Are you updating a motor overload protection or a motor controller? You can use a motor controller as overload protection [430.39]. It might make sense in this application to combine the two functions in one device.


Safety
If a safety concern poses an immediate threat (e.g., a gas leak), stop working. Alert others in the area, and then leave the space. But what if you're unsure that there really is a threat? What if you don't have enough information to know it's not safe to work there? All you need is a reasonable doubt. If in doubt, get out.

As with a known danger, immediately alert others so they know to leave the area. Then, report the danger to the area supervisor. Next, report to your supervisor and ask what you should do while the problem is being investigated.

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VISIT THE EC&M e-TRADESHOW
Look for these FREE live conferences, scheduled for THIS MONTH:

Wednesday, March 19, Noon EST, 9 a.m. PST "Poor Working Drawings: The Construction Industry's Prevailing Problem," presented by John DeDad
EC&M's senior director of editorial will tap into his 40 years of construction experience and detail his interviews with owners, architects, professional engineers, and contractors about the poor working drawing problem. He'll also cite specific examples of the shifting of responsibilities and propose recommendations to help ease the severity of the problem.

Monday, March 24, 10 a.m. EST and PST: "Harmonic Solutions: Side-by-Side Comparisons," presented by Dan Carnovale, P.E., Eaton Corp.
Learn about side-by-side comparisons of various harmonic mitigation technologies, based on testing conducted in a test lab specially constructed to evaluate all of the major categories of harmonic solutions for industrial and commercial power systems. See the results of this testing, including considerations for generator applications, harmonic resonance, and the application of phase shifting. Energy savings observations will also be discussed. Video recordings of the testing will be included.

Coming soon:

• "Understanding Electrical Safety and PPE Selection"
• "Implementing an Arc Flash Safety Compliance Program"
• "Preparing an Arc Flash Hazard Study"

Visit the many exhibitors in this virtual tradeshow and take a look at the On-Demand Theater, where you can view past online conferences 24/7/365. Go to http://www.ecmweb.com/etradeshow/index.html for information on accessing the EC&M e-Tradeshow and visiting the On-Demand Library.

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Quiz Answer
Answer to Electrical Troubleshooting Quiz
For one motor, you can do a simple cost analysis. Sending out that 5-hp sump pump motor that failed after 20 years isn't cost-effective, but getting a forensic report on a failed 750-hp motor is. The question implies there's a point in between, perhaps at 75 hp and below, where the investment isn't worthwhile. However, it isn't that simple.

Suppose you have a large, multistage conveyor system and one of the five dozen non-critical 10-hp conveyor motors fails every few weeks? The plant still runs, but you have a sort of rolling production outage, and it's persistent.

Here, the cost of a single 10-hp motor doesn't justify the expense of a forensic exam. The real issue is the persistence of motor failure in the system, which isn't acceptable. You must determine the root cause. Persistent failure may also be the proverbial canary in the mine (e.g., power anomalies due to transformer overload are killing the motors).

A forensic exam will identify a cause or quickly eliminate several possibilities. Consider how quickly a forensic exam can reveal, for example, motor lubrication errors. Without that exam, you'd be chasing phantom causes for months rather than fixing the problem.