Archive | June


6:00 am
May 1, 2005
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Power Quality Testing Can Reduce Costs

Predictive maintenance (PdM) techniques are commonly used on motors and drives. But how often is the power to the equipment inspected? Adding basic power quality measurements to equipment maintenance procedures can head off unexpected failures in both the equipment and the power system.

Cost savings
Insurance claims data in the NFPA 70B maintenance standard show that roughly half of the cost associated with electrical failures could be prevented by regular maintenance. A study published in IEEE 493-1997 says that a poorly maintained system can attribute 49 percent of its failures to lack of maintenance.

To determine the cost of a failure, it helps to consider three key categories:

• Lost income (gross margin) due to downtime

• Cost of labor to troubleshoot, patch, clean up, repair, and restart

• Cost of damaged equipment and materials, including repairs, replacements, and scrapped material.

Integrating power quality into PdM
Unlike a comprehensive electrical system survey, predictive maintenance power quality focuses on a small set of measurements that can predict power distribution or critical load failures. By checking the power quality at critical loads, the effect of the electrical system up to the load can be seen. Predictive maintenance inspection routes probably already include motors, generators, pumps, A/C units, fans, gearboxes, or chillers on site.

Voltage stability, harmonic distortion, and unbalance are good indicators of load and distribution system health and can be taken and recorded quickly with little incremental labor. Current measurements can identify changes in the way the load is drawing. All of these measurements can be taken without halting operations and generate numbers that can easily be entered into maintenance software and plotted over time.

For each measurement point or piece of equipment, determine what limit should trigger corrective action. Limits should be set well below the point of failure, and as time goes on limits may be tightened or loosened by analyzing historical data. The appropriate limits depend somewhat on the ability of the loads to deal with power variation. But for most equipment, the maintenance team can devise a set of house limits based on industry standards and experience.

Good voltage level and stability are fundamental requirements for reliable equipment operation.

• Running loads at overly high or low voltages causes reliability problems and failures. Verify that line voltage is within 10 percent of the nameplate rating.

• As connections in the system deteriorate, the rising impedance will cause insulation resistance drops in voltage. Added loads, especially those with high inrush, also will cause voltage decline over time. The loads farthest from the service entrance or transformer will show the lowest voltage.

• Neutral to ground voltage indicates how heavily the system is loaded and helps track harmonic current. Neutral to ground voltage higher than 3 percent should trigger further investigation.

Voltage sag count
Taking a single voltage reading tells only part of the story. How is the voltage changing during an hour? During a day? Sags, swells, and transients are short-term variations in voltage. The voltage sag (or dip) is the most common and troublesome variety.

Voltage sags are momentary reductions in rms voltage from 1 cycle to 2 minutes. Loads may be added without notifying plant management, and these loads may draw down system voltage, especially if they draw high inrush currents. Also, as electrical systems age, the impedance of the system may increase, making the system more prone to voltage sags.

Sags indicate that a system is having trouble responding to load requirements; significant sags can interrupt production. Voltage sags can cause spurious resets on electronic equipment such as computers or controllers, and a sag on one phase can cause the other two to overcompensate, potentially tripping the circuit.

Sags have several dimensions: depth, duration, and time of day. Utilities use a special index to track the number of sags that occur over a period of time. To gauge the depth of the sags, they count how often voltage drops below various thresholds.

The longer and larger the voltage variations, the more likely equipment is to malfunction. For example, the Information Technology Industry Council (ITIC) curve specifies that 120 V computer equipment should be able to run as long as voltage does not drop below 96 V for more than 10 seconds or below 84 V for more than 0.5 sec.

The main cost factors of voltage sag are lost income due to computer reset, control system reset, variable frequency drive (VFD) trip, and shortened life of a backup power system’s uninterruptible power system (UPS) due to frequent cycling.

For example, assume a voltage sag causes a VFD on a conveyor system to trip offline at least once a year. No income is permanently lost, but 10 hourly workers have to work 4 hr to make shipments at $30/hr, which includes overtime. Added labor = 10 people X 4 hr X $30/hr = $1200 annually

Motors, VFDs, UPSs, panels, or power distribution units (PDU) serving computer equipment or industrial controls should be checked for voltage sag.

How much voltage sag can be tolerated? Most loads will operate at 90 percent of nominal voltage. The ITIC curve suggests that single-phase computer equipment loads should be able to ride through drops to 80 percent of nominal for 10 sec and 70 percent of nominal for 0.5 sec.

Increasing current
Current measurements that trend upward are a key indicator of a problem or degradation in the load. While equipment is running, monitor phase, neutral, and ground current over time. Make sure none of the currents are increasing significantly, verify that they are less than the nameplate rating, and keep an eye out for high neutral current, which can indicate harmonics and unbalance.

As insulation deteriorates it begins to leak. Loads will draw slightly higher current as they age and they may send some of this leakage current into the grounding system. Faults within the equipment also may cause high ground current. The best way to check insulation is by periodically checking equipment with an insulation tester. But equipment also can be checked while it is in service by monitoring all of the currents (phase, neutral, and ground) to make sure none of these is increasing significantly over time.

Excessive phase currents can further damage insulation and overheat the load, resulting in a shortened life of the load. Overcurrent will cause protection devices to trip, resulting in unscheduled downtime. Excessive ground current can create unsafe voltages on metal chassis, cabinets, and conduit.

Any critical load, but especially motors, VFDs, and transformers, should be checked for increasing phase current.

Costs come from premature motor failure and lost income due to overcurrent protection devices tripping. As an example, assume the failure of a pump motor each year costs $7000 to replace and causes a $2,500,000/yr continuous process to be shut down for 10 hr. Assume it takes two people 6 hr to clean and restart the process at $50/hr each.

Lost income = 10 hr X ($2,500,000/(365 days/yr X 24 hr/day)) = $2853

Motor replacement = $7000
Clean and restart = $600
Total cost = $10,453 annually

The nameplate rating of the load should never be exceeded. If the phase current being drawn by a load is tracked over months or years, a change in the current should be evident.

Voltage unbalance
In a three-phase system, significant differences in phase voltage indicate a problem with the system or a defect in a load. Voltage unbalance can cause three-phase motors and other three-phase loads to experience poor performance or premature failure because of mechanical stresses in motors due to lower-than-normal torque output, higher-than-normal current in motors and three-phase rectifiers, and unbalance current will flow in neutral conductors in three-phase wye systems.

Unbalance is tracked in percentages. The negative sequence voltage (Vneg) and zero sequence voltage (Vzero) together identify any voltage asymmetry between phases. Using a power quality analyzer to do the math, high percentages indicate high unbalance. European Union power quality standard EN50160 requires Vneg to be less than 2 percent.

The major costs resulting from voltage unbalance are associated with motor replacement (labor and equipment) and lost income due to circuit protection trips.

For example, assume the cost to replace a 50 hp motor each year is $5000 including labor. Assume 4 hr of downtime per year with income loss of $6000/hr.

Total cost: $5000 + (4 X $6000) = $29,000 annually

The EN50160 standard requires voltage unbalance, as a ratio of negative to positive sequence components, to be less than 2 percent at the point of common coupling. NEMA specs call for less than 5 percent for motor loads. Consult user manuals for other equipment.

Voltage harmonic distortion
Harmonic distortion is a normal consequence of a power system supplying electronic loads such as computers, business machines, electronic lighting ballasts, and control systems. Adding or removing loads from the system changes the amount of distortion, so it is a good idea to regularly check harmonics.

Harmonics cause heating and reduced life in motor windings and transformers, excessive neutral current, increased susceptibility to voltage sags, and reduced transformer efficiency.

As current harmonics interact with impedance, they are converted into voltage harmonics. Total harmonic distortion (THD) is a sum of the contributions of all harmonics. Tracking voltage THD over time will help determine if distortion is changing. For voltage harmonics, IEEE 519 recommends less than 5 percent THD.

Harmonic distortion can cause:

• High current to flow in neutral conductors.

• Motors and transformers to run hot, shortening their lives.

• Increased susceptibility to voltage sags, potentially causing spurious resets.

• Reduced efficiency of transformer or a larger unit is required to accommodate harmonics.

• Audible noise.

The major costs of harmonic distortion are associated with shortened life of motors and transformers. If the equipment is part of production systems, income may be affected as well.

For example, assume the cost to replace a 100 kVA transformer is $7000 including labor each year. Assume 8 hr of downtime each year with income loss of $6000/hr.

Total cost: $7000 + (8 X $6000) = $55,000 annually

Motors, transformers, and neutral conductors serving electronic loads should be checked for harmonics. Voltage distortion should be investigated if it is more than 5 percent on any phase. Some current distortion is normal on any part of the system serving electronic loads. Monitor current levels and temperature at transformers to be sure they are not overstressed. Neutral current should not exceed the capacity of the neutral conductor.

These measurements can help uncover hidden costs, protect equipment from damaging conditions, reduce unscheduled downtime, and improve systems performance.

Information supplied by Wade Thompson, power quality specialist, Fluke Corp., P.O. Box 9090, Everett, WA 98206; (800) 443-5853

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6:00 am
May 1, 2005
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RSS for Maintenance and Reliability

You have probably heard about blogs (weblogs) by now. For example, features nine different maintenance-related blogs by various authors, including a terrific motor blog series by Howard Penrose, Ph.D. More than likely you have heard about other more popular political blogs, like the one that uncovered the recent CBS news debacle.

This column is not about blogs but deals with one of the aspects of a blog that makes the technology unique called real simple syndication (RSS).

According to, RSS is a format for syndicating news and the content of news-like sites, including major news sites like BBC and Wired, news-oriented community sites like Slashdot, and personal weblogs. But it is not just for news. Almost anything that can be broken down into discrete items can be syndicated via RSS—the recent changes page of a wiki or the revision history of a book. Once information about each item is in RSS format, an RSS-aware program can check the feed for changes and react to the changes in an appropriate way.

A program known as a feed reader or aggregator (see sidebar) can check RSS-enabled Web pages on behalf of a user and display any updated articles that it finds. RSS saves users from having to repeatedly visit Web sites to check for new content or be notified of updates via e-mail. It is common to find RSS feeds on most major Web sites, as well as many smaller ones.

Many weblogs make content available in RSS. A news aggregator can help you keep up with all your favorite weblogs by checking their RSS feeds and displaying new items from each of them. Audio information also is available via RSS and is known as a podcast (as in “iPod + broadcast”) or audioblog.

An orange rectangle with the letters XML ( ) or RSS () is often used as a link to a site’s RSS feed. Click the icon and a page will appear with XML programming code on it. Ignore the page content and simply copy and paste the URL that is displayed in your browser address window. Add the URL to your news reader in order to be “subscribed” to the RSS feed.

I was recently involved with a software project similar to a CMMS implementation and the manager used Basecamp as the project management tool. I could (and may) devote an entire column to online project management software; however, now I will simply point out that I used the Basecamp software RSS feed (added to my MyYahoo! start page—see Internet Tip) to stay current with project communication, milestones, key contacts, and feedback. It was one of the best projects I have worked on and all parties were remote. The project was a raging success.

I also like to track comments and new postings on Maintenance Forums’ threaded discussion boards so I added the site’s RSS feeds to my Tristana news reader (see sidebar) and to my MyYahoo! start page. It saves me from having to check by e-mail or having to visit the Web site. Once I have clicked a link, it changes color to let me know I have already read it.

RSS is not just a way to get news and blogs delivered to your desktop; it is actually a more useful e-mail alternative as all related feeds are organized and archived for easy access when a look back is required.

We are collecting links to all maintenance-related RSS feeds. Please e-mail me if you know any good feeds we can share.

Terrence O’Hanlon, CMRP, is the publisher of He is the director of strategic alliances for the Society for Maintenance & Reliability Professionals (SMRP). He is also the event manager for CMMS-2005, the Computerized Maintenance Management Summit on July 26-29, 2005, in Indianapolis, IN


These readers offer free download and deliver directly to your desktop.

Tristana Maintenance News Reader




If you are one of the millions who have Yahoo e-mail accounts or use Yahoo Instant Messenger, then you probably have a start page that you can customize with news, new movie releases, company stock news, and weather reports.

In the old days of the Web (more than 6 months ago) you could add only Yahoo-supplied content to your MyYahoo! page. Now with the wonders of RSS and XML you can add any information that offers an RSS feed.

To add RSS content to MyYahoo!:

1. Log into your start page.

2. Scroll to the bottom of the page and look for the blue and white “Add Content” button.

3. A search box will appear with a Find button.

4. Click the “add RSS by URL” link to the right of the find button.

5. Copy and paste your RSS URL into the box and click “Add.” You get the RSS feed you want by clicking the orange RSS/XML icon and copying the resulting URL into your clipboard.

6. You can rearrange the order and where the RSS feed appears on your MyYahoo! page as well.

If you do not have a MyYahoo! account, get one; it is free and includes a free 2 GB e-mail account (that is not owned by your employer) and lots of other awesome tools like adding your own RSS feeds to your customized start page.

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6:00 am
May 1, 2005
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Develop Workers To Be Responsible, Motivated

Management within many maintenance organizations views its workforce as “resources” that provide the hands necessary to perform a function or to complete a task. In most instances, the use of these workers as resources has been well planned in order to obtain the maximum results, while little consideration has been given to the needs of the whole person.

This perception of workers has only increased the division between management and staff (salary and hourly) personnel. It also tends to place less thought or consideration on the motivation of the workers.

Development of workers must be considered and emphasized from the moment of initial employment. Attention must be placed on those areas that will prepare and motivate the worker to excel. This may include a better application of the skills and talents possessed by the individual or the assignment of additional responsibilities based on the individual’s technical skills. Assigning tasks of lesser capabilities and little, if any, responsibility will soon lead to poor quality of workmanship and job dissatisfaction.

Each organization should currently possess or create a vision statement for the development of its workers. This statement should plainly state how the organization will support the continuous improvement of its workforce at the group as well as the individual level.

The vision may include areas such as rewards and recognition for performance and the treatment of workers as individuals, with respect, and with dignity. Workers should be viewed as both teachers and students and should be given the freedom to act on their own (within company and management constraints).

Development challenges
A typical maintenance workforce is made up of highly skilled individuals. These workers (who have completed an organizational apprenticeship program and gained working experience with the equipment) represent a significant monetary investment by the company. This fact should force the organization to look upon the workers as a valuable asset, just as it normally considers a piece of equipment as a valuable asset. The workers too must be respected and continuously improved.

Studies have shown that many workers are assigned tasks that require limited skills or involvement, even though the workers’ potential for improvement may be somewhat greater. These studies indicate that many workers spend less than one-fourth of their time performing work compatible with their skills and capabilities. This type of management behavior soon leads to unmotivated workers who do not strive for additional responsibility or greater involvement in the organization.

Development opportunities
Motivation of maintenance workers must be the forethought of each manager. Workers should be developed steadily throughout their careers so the assigned work is interesting and challenging. They should always be provided with a sense of achievement.

The manager should plan to develop workers in both their skills and their responsibilities. Skills development may begin with acceptance into an apprenticeship program or by training to be a “multi-craft” worker.

As workers’ skill levels increase, their levels of responsibility also should increase. This may begin with the requirement to inspect and report on one’s own work and progress to instructing others in the performance of the tasks.

Workers must be hired and retained to meet the structural, process, and production needs of the organization. To accomplish this, the organization must develop and conduct training based on the industry, the processes used in production, the equipment in use (production and maintenance), and the maintenance and technical skills required to achieve the established efficiency and production-level requirements.

Many apprenticeship programs will provide the training required to acquire the necessary technical skills, but that training must be modified to include the requirements of the specific organization. Training which would provide for personal development also should be considered, even though the subject matter may not be technically related. Also, the training program should provide for the development of skilled, experienced workers into the position of trainers, transferring their skills and experiences to other workers or other work groups.

Development structure
During the development of workers, their views or perceptions must be considered and monitored. Once selected for training, individuals may be placed in positions in which they are not comfortable and/or willing to accept. This may include the recognition placed upon them due to their selection, the increased exposure brought on by the training, the movement from centralized to decentralized decision making, or becoming a group leader vs a group member. Workers must be observed during development to ensure that any situation that may derail the process is addressed and a remedy is found as early as possible.

The environment in which the development of the worker occurs will have a large effect on the outcome. This development process should be viewed as a re-education process for the individual. Trends and habits, which have been practiced for years, will be altered. An environment must be presented which is conducive to learning and to helping change the attitudes of the workforce as they relate to training.

This does not mean that only the proper physical environment must be present. The proper mental environment will be just as, if not more, important. A healthy training environment will allow for raising the skill levels of the workers, raising the workers’ confidence, raising the workers’ responsibility and authority levels, developing team building traits, developing a positive attitude, and demonstrating technical achievements.

There is not one development program that will fit every organization or every individual. Each organization due to size, product, or internal and external factors must create its own unique program. Areas which should be considered during this creation include the length and depth of training required by each individual, the expectations upon completion of the training, subject matter to be taught, “pay-for-skills” expectations, levels of recognitions (local or higher), provisions for individuals who cannot or do not complete the training, and the pace of training (time frame).

The one area that will have the most effect on the outcome of the development plan is the individual himself. Some may see the training pace as too slow and become bored and uninterested. Others may see it as too fast paced and become anxious about their ability to keep up. Some may find the subject matter too difficult to comprehend, while others will find it too basic or elementary. Alternative methods of training must be considered in order to continuously motivate the individual.

Development approach
The reason for the development of workers should be to create a trained and motivated workforce that can and desires to contribute to the efficiency and effectiveness of the organization. When workers are given responsibility, freedom to make decisions, and the power to carry through on their actions, they will be eager to contribute. When they are treated with respect and dignity, they will become more motivated to participate in organizational improvement activities.

The areas that should be included in the workers’ development plan to increase this motivation should be extended from the shop floor up toward management and from management downward toward the workforce.

As the skills and capabilities of the workers continue to improve, the development plan, like the workers, should be under a continuous improvement process. This will ensure that the plan remains an effective tool in the development of the workforce.

Mike Willard is senior consultant at Life Cycle Engineering Inc., 4360 Corporate Rd., Charleston, SC 29405; (843) 744-7110

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6:00 am
May 1, 2005
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Evangelizing Reliability

Keeping an eye on the Internet is an enjoyable perk of my job as editor. One of the gurus I watch is Jakob Nielsen, an expert in the usability of user interfaces to software applications and Web sites. The title of one of his recent newsletters, “Evangelizing Usability: Change Your Strategy at the Halfway Point,” grabbed my eye immediately because I misread it as Evangelizing Reliability.

As I read it, I saw that when purposely substituting reliability for usability, it still made a lot of sense. See what you think. Check out the following paragraphs (with appropriate subsitutions made) taken from the article archived on Nielsen’s site.

The evangelism strategies that help a reliability group get established in a company are different from the ones needed to create a full-fledged reliability culture.

The approach that takes your company from miserable reliability to decent performance is not the one you’ll need to get from good to great.

A company progresses through a series of maturity levels as reliability becomes more widely accepted.

In the early maturity stage, few resources are available and the company is not truly committed to reliability. The key word for early evangelism is to be opportunistic in allocating your scarce resources. You can’t follow the recommended reliability process in all its glory because your organization lacks the commitment required. Instead of fighting windmills, go for the easy wins.

Luckily, a company without a systematic reliability history will have much low-hanging fruit for you to pick. Once these easy reliability wins generate substantial business wins for the company, management is usually interested in funding an official reliability group . . . with a manager, a charter, and a budget to perform reliability activities.

As the company matures, more resources become available for reliability, but some prioritization is still needed. At the previous stage, priorities were opportunistic; they must now be more selective. Rather than chase easy wins, you must build spectacular wins for reliability to convince executives to move the organization to the desired goal state.

At this point, the strategy should be to focus on high-impact projects where the benefits of substantial reliability improvements will have enormous monetary value and high visibility for senior executives.

The way forward is to focus on a few high-impact projects, and make them smash hits.

Robert C. Baldwin, CMRP, Editor

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6:00 am
May 1, 2005
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Refurbishing Aged MCCs Proves Beneficial

In 1999-2001, the New Jersey International & Bulk Mail Center (NJI&BMC) in Jersey City, one of the largest United States Postal Service facilities, was concerned about its eight 33-year-old motor control centers (MCCs). Events forced a decision to pursue options for replacing or refurbishing the 276 cells that provide power primarily to 58 heating, air conditioning, and ventilation air handling units (HVAC AHUs) for the 1.8-million-sq-ft facility.

The in-house maintenance project was completed in November 2004 without any plant shutdowns, injuries, or delays in mail processing operations or exceeding the allotted budget. The project improved safety and security for employees and facility equipment, extended overall life of the MCCs, enhanced skills of the craft crew and employees, and saved an estimated $1.8 million.

NJI&BMC usually processes more than 1 million pieces of mail daily, on a 24 hour/7 day basis. The mail volume has increased significantly for the past 20 months because of the heavy mail volume from Iraq, and other military activities.

The largest of 21 bulk mail centers, the facility’s main buildings have about 1100 conveyors, and parcel sorting and sack sorting machines, that would stretch up to 25 miles if placed end-to-end. After being sorted, mail is distributed to various postal facilities and international shipping docks on a daily basis from 305 truck bays.

In 1999-2001, the facility experienced three incidents where aged components in various MCC cells malfunctioned, resulting in minor explosions and fire. Maintenance personnel were successful in containing the fires and preventing any additional property damage or any personnel injuries. Based on these experiences, it was decided to explore cost-effective options for replacing or refurbishing the 276 buckets.

Option one: replacement


33-year-old MCC before refurbishment


MCC at completion of project


Internal components of original MCC


Internal components of refurbished MCC



Option one was the traditional and easiest option—procuring and installing new MCCs. This would require intensive on-site field work including disconnecting approximately 3000-4000 wires, removing eight MCC cabinets from the fourth floor penthouse location, reconnecting all load and line sides of the MCC cells, and then testing, validating, and accepting all field wiring. This would also result in costly electricians’ field hours and overtime.

An electrical engineering consultant conservatively estimated the cost of replacing all eight MCCs/276 cells at approximately $1.5 million: $560,544 for material, $680,000 for labor (disconnecting, removing, disposing, reconnecting, and testing 276 cells), and $250,000 for architect/engineering services, project management, design, engineering, contingency, and construction. Other incidental costs, such as downtime, utilization of facility resources, restoring the facility to normal conditions, and shutdown costs, were not included in this estimate.

This option would require several planned shutdowns. Since the facility operates on a 24/7 basis, any inadvertent switching actions or faulty wiring would impact the routine and severely hamper mail processing operations. Scheduling and coordinating active MCC outages in a safe and secure manner also would require additional maintenance resources and manpower. Facility shutdown costs, based on past experience, are approximately $75,000/hr, and directly impact revenue.

Option two: revitalization
The possible plant shutdowns, high costs, and the potential for jeopardizing safety and security of employees and equipment forced investigation of an alternate option. Discussions with the maintenance technical and craft personnel who ultimately would be responsible for any work led to the decision to examine revitalization and refurbishment of the internal consumable components of the MCCs. This option immediately relieved the staff from scheduling and coordinating outages of complete MCCs, and there would be no plans for any restoring and normalizing of plant operations.

The estimated cost for this option was $435,000. The Purchasing and Supply Chain Management office in Windsor, CT, reviewed, analyzed, and processed this concept for final installation and estimated that the project saved $1.8 million for USPS.

One of the main reasons for this significantly lower cost was that this option re-used nonmoving existing components (bus work, metal frames, power and control cables, conduits, cable trays, approximately 3000-4000 external wires, etc.) without disrupting or jeopardizing any field wiring. This concept replaced all consumable items and moving parts such as contactors, relays, fuses, circuit breaker, selector switches, indicating lights, and internal wiring.

Furthermore, the plan indirectly enhanced in-house skills by using the facility’s own employees. From the beginning, the craft personnel were interested in replacing the aging cells. They actively participated in configuring component layout, testing experimental cells, and modifying wiring and component layout that enhanced safety and ease of maintenance. They also participated in ranking and selecting the supplier for the refurbished buckets.

Field-testing prototype cells
Since this retrofitting concept had not been undertaken on such a large scale in any postal facility or any other industrial site, the maintenance staff asked three suppliers who had experience in completely re-building MCC cells to make prototype test cells and install them at the site for actual field testing. Maintenance employees prepared and completed design, wiring diagrams, and sketches to suit the existing field wiring and layout. They removed three existing cells, gave them to the suppliers, and asked them to retrofit for variable frequency drive (VFD) applications. The cells were chosen because they were more complex, congested, and difficult to work on.

The retrofitted cells were field tested for approximately 4 months. The original VFD cell design was problematic, so the cable routing from VFD to contactor, starter, and motor was reconfigured. All suppliers provided new contactors, LED indicating lights, control transformer, breaker, control switch, timer, wiring, stabs, etc. However, the component layout and wiring configuration varied per supplier’s preference and design.

Selecting a supplier
After completing the initial field testing and validating the concept, the Purchasing and Supply Chain Management office prepared and issued a complete bid solicitation package, including scope of work and terms and conditions. In conjunction with procurement personnel, the maintenance team evaluated bids. Craft personnel provided primary input, specifically looking for ease of maintenance and maintaining plant safety requirements. They provided significant recommendations on maintenance issues regarding performing PM or replacing the cell.

From a previous project—replacing 150 600V FPE circuit breakers—the team learned the value of selecting a supplier within the metropolitan area of the facility. Its 24/7operation demands immediate services in instances where the supplier is needed on-site for emergencies.

Five team members—a procurement specialist, the electrical engineer, the preventive maintenance engineer, the manager of maintenance operations, and an electronic technician—actively participated in ranking and selecting Gavan-Graham Electrical Products Corp., a local panel board assembler who agreed to meet requirements and satisfy terms and conditions as specified in the bid solicitation package. The company was helpful in satisfying and accommodating changing schedules and site-specific requests.

Cells removed
In the last week of November 2002, the maintenance team removed approximately 50 existing cells and the supplier picked them up for retrofitting. At the factory, technicians removed all internal components, discarded all wiring, and cleaned, anodized, and painted the cell structures.

Based on the approved wiring schematic, the technicians rebuilt the cells, using new control transformers, new LED indicating lights instead of regular bulbs, control selector switch, contactors, timers, solid state relays, fuses, plug in terminal blocks for both power and control wiring, etc. This batch of cells was to be retrofitted for VFD applications.

Designing a test-bench cell


All 276 cells were bench tested at the factory to ensure workability.




The maintenance staff wanted to standardize a unique testing procedure for each of the 276 cells. Using technicians to test individual wiring induced human errors and higher costs. The supplier resolved the problem by designing and assembling a separate test-bench cell in the factory to bench test all wiring and to simulate various operating conditions displaying proper LED lights. The supplier also agreed to test every cell prior to final shipment to NJ&BMC. This innovative idea was beneficial for the maintenance crew because it reduced significant manpower and field wiring headaches at NJ&BMC.

On February 11, 2003, the team completed acceptance testing of the test-bench cell at the factory. The electronic technician selected two random cells from the 30 cells that were ready for final shipment. One cell failed the testing protocol and required wiring changes. This test demonstrated various operating parameters that were validated by the red, green, and white LED lights. Bench testing each of the 276 cells prior to final shipment prevented any inadvertent wiring errors and damage at NJ&BMC.

Replacing MCC cells
Removing existing cells from the working MCCs and installing retrofitted cells in a safe and secure manner needed close coordination among various departments because of the major hurdles to overcome. The team realized that retrofitting 276 cells would be difficult and would take more time than earlier estimated, especially since it was accomplishing this work while the facility was operating at its optimum capacity, and without imposing any major impact on mail processing operations.

During the second week of February 2003, the team successfully completed installing the first set of 30 VFD cells without any problems, and continued replacing additional cells as feasible. Initially, it had minor problems retrofitting two cells because the back stabs did not align with MCC buses. The supplier noted and corrected deficiencies immediately.

As indicated previously, certain portions of this job were more complicated. When staff opened the size 5 starter’s buckets for inspecting internal components and for disassembling one of the largest cells, it could not pull out the buckets because the main breakers were directly connected to the main MCC buses. These buckets, as compared to other buckets, did not use easy pull-out stabs. Instead, the circuit breaker was directly connected to main buses via heavy cables. Power was shut down for removal and installations of these buckets.

Furthermore, reconfiguring and rerouting load and line side power cables and auxiliary control cables were challenging for the on-site crew. It also found that all of the size 5 buckets were not identical as previously thought. The supplier had to rewire each bucket to suit the individual bucket wiring design, and craft personnel had to reconfigure load and line side cables.

The retrofit concept was challenging and difficult for maintenance because the maintenance function, in general, is mandated to conduct periodic PM and to maintain the buildings, equipment, and grounds. Usually an architect/engineer would design, engineer, manage construction, and complete installation. Instead, maintenance staffers managed maintenance resources successfully and completed design, engineering, removal, and installation themselves. Project-related work such as this is considered lower priority and usually takes longer to complete.


External and internal views of combined small starters cells




Combining small starters
Approximately 100 size 1 starters were designated for exhaust fans and door heaters. The exhaust fan motors, in general, were drawing 0.9-4.2 A, whereas the door heater fan motors varied from 4-10 A. It was decided to combine and standardize two lower-A-drawing cells into one cell. This combined cell would be retrofitted with one circuit breaker, two control switches, two sets of LED indicating lights, separate wiring, two contactors, and one control transformer. The electrical architect/engineer (Triad Consulting Inc.) verified that the short circuit rating and other safety parameters were within the acceptable ranges, and the combining concept would increase the number of spare starters by 50 percent.

In the last week of March 2003, the supplier retrofitted one of the prototype combination cells and it was installed in the MCC-F-1, 6A for bay door heater fan motor 37 and 38. This concept was proven successful, and resulted in increasing existing power distribution capability in the MCCs by approximately 50 percent. The facility gained these advantages without any major modifications to the MCC cabinets, and at minimal cost to the USPS.

From March to August 15, 2003, there were no problems with this experimental cell and the team continued combining cells where feasible. As of April 2005, there have been no operational problems with these combined starters cells.

Based on its limited experience, the maintenance team recommends the following key items when replacing/retrofitting MCCs:

• Encourage maintenance craft personnel input from the beginning of any retrofitting on-site projects.

• Complete thorough investigations of existing equipment, inspect and validate consumable and nonconsumable parts.

• Realize that retrofitting and replacing internal MCC components can save capital cost and maintenance resources and extend life expectancy of the equipment.

• Perform extensive field testing of prototype cells on-site prior to authorizing additional work.

• Assess need for an on-site standby power source, if shutdown is inevitable.

• Emphasize on-site immediate response from the supplier when necessary.

• Prepare detailed planning and step-by-step procedures to minimize operational impact.

• Review safety and environmental issues with on-site experts prior to initializing the project

Checking, validating field testing, and revitalizing the 33-year-old MCCs did improve life expectancy, enhance safety and security, reduce maintenance resource requirements, improve maintenance skill sets, and lower overall costs.

The authors appreciate the support from the following organizations and USPS personnel:USPS NJ&BMC: Frank P. Tulino, plant manager; Edward P. Pfeiffer, preventive maintenance engineer; Tom Finan, electronic technician; senior maintenance operations supervisors; and managers of maintenance operations. Windsor, CT, P&SCM: William F. Blazinski and Manager Robert A. Bress. USPS NewYork area maintenance support: Leon Roszkowski, Nick Borg, and Manager Guy Miata. Gavan-Graham: Emerson Crooks. Triad Consulting: Paul Witwick and Ron Regan.

Joseph C. Pearson has been the manager of maintenance at the United States Postal Service’s New Jersey International & Bulk Mail Center for the past 15 years. The facility’s maintenance department consists of approximately 500 managers, engineers, and craft employees. Dilip A. Pandya has been the electrical engineer at NJ&BMC for the past 5 years and manages electrical requirements for the facility. He is responsible for investigating and implementing innovative cost-effective technologies. He can be contacted at (201) 714-6727

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6:00 am
May 1, 2005
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2005 Vibration Monitoring and Analysis Guide

Machinery vibration monitoring and analysis are fundamental to predictive maintenance and continuous plant improvement. Here is information to help you with a vibration program.


Technician uses laser velocity transducer to take vibration readings on rear side dryer bearings. (Photograph courtesy L&S Electric Inc.)

The principles of monitoring the health of plant machinery by checking vibration are straightforward. All operating machines vibrate. Since an increase in vibration almost always accompanies deterioration in running conditions, it is possible to gain information about a machine’s condition by monitoring vibration levels.

The overall level of vibration indicates the general condition of the machine; vibration analysis can be used to determine the cause of vibration, including such factors as unbalance, misalignment, or bearing defects.

Today portable data collectors and online monitoring systems are used to gather data from hundreds or thousands of points to allow computer analysis of equipment health.

Ideally, this information could be integrated via a computerized maintenance management system or an enterprise asset management system with other asset health data for an overall picture of total plant and operations equipment condition.

With expanded use of the Internet and access to wireless technology, remote monitoring of machinery and data transmission is getting easier and quicker. All segments of an organization, including operations and management, can share information and access data. This works to ensure that assets are used in the best manner possible, with minimum costs, to provide continuous improvement in plant operations and maintenance functions.

Selecting technology
Terrence O’Hanlon of suggests the following questions be addressed when a company is in the selection process for new technology:

  • How do the vibration analysis and other PdM technologies fit into the overall maintenance and reliability program? Is there a systematic process for determining the most critical equipment to monitor?
  • Can the data be interfaced with the primary information system (CMMS or other) to generate work orders?
  • How much training is required to become proficient?
  • How much is the total cost of ownership (TCO) for the life of the vibration analyzer? Companies may charge a significant sum of money for software maintenance year after year.

Approaching management
To purchase new vibration monitoring technology, maintenance managers have to present a business case for the equipment to upper management. Suppliers in this update offered helpful advice for strengthening managers’ appeals.

A financial analysis or ROI study is imperative, noted OROS and the Vibration Institute. Nelson Watson of Watson Engineering, Inc. added, “Take the time and effort to perform an economic justification for the new investments. The investment must be cost effective and meet company return on investment requirements.”

Further advice came from William E. Johnson of Engineering Concepts, LLC. He urged managers to “identify all costs associated with all maintenance functions, especially repeat repairs and/or breakdowns. How many items do you have to maintain in inventory to replace broken or failed equipment? Does mechanical electrical failure affect production rates or increased scrap rates? If it does, then determine the cost and how that affects your product cost margins.

“This is a lot of paper work, but it is extremely necessary to justify the added expense of new equipment or consulting services. You will be surprised how repeat failures and even frequent repairs will affect the bottom line.”

“The PdM manager should be able to demonstrate an increase in uptime/availability due to his vibration monitoring program,” noted Martin T. Morrissey of Monarch Instrument. “He must be able to show an improvement to the bottom line by being able to keep equipment running longer, safer, and without unscheduled downtime,” added Lou Morando of SPM Instrument Inc.

“All benefits must be presented in dollar terms. What can you learn or achieve with the new technology that you could not achieve before, and how can that help increase production, decrease downtime, or generally save money for the organization,” summarized Jason Tranter of Mobius North America.

Besides documenting current efforts well, Mary Ann Ford of SKF Reliability Systems noted managers should “relate results to key performance indicators, such as mean time between failure (MTBF) numbers, cost savings, unexpected failures over time, etc.”

Advancements in technology
The case to management may be made easier due to advancements in the technology in recent years. “Because of the simplicity of the new technology, useful and effective data can now be collected by lesser skilled personnel for reliability specialists to analyze. In addition, the new technology is more affordable and easier to use—providing for a faster ROI,” said Steve Reilly of Design Maintenance Systems Inc.

“Products on today’s market offer much more flexibility and power than those from the past. Vibration analyzers are now available offering over 100,000 lines of resolution allowing better detection of machinery faults. These tools have built-in features to help the user decipher different machinery problems, within the field machinery fault frequencies, bearing frequencies, and alarm levels. Software programs are now more user friendly and assist in the analysis of data,” offered Greg Lee of Ludeca Inc.

A simple piece of advice came from David Poffenbarger of Fastrack Technologies: “Start a small program that can be run efficiently. As successes come, expand as necessary.” And there is another benefit of a vibration monitoring program: “An important, but often undiscussed, benefit of regular condition monitoring is that it forces personnel to look at operating equipment. Many incipient problems are identified simply by having somebody stand and wait for a data collector to perform its job,” noted Doug Smithman of EMP Engineering Services, Inc.

As Skip Morrison of Prognost Systems, Inc. summarized, “Investments in (proper) on-line monitoring technology have proven that a clear reduction in the cost of operating and maintaining the overall process facility can be achieved in the short term. On-line monitoring will improve plant safety by mitigating the risk of catastrophic machine damage, improve production throughput by reducing unscheduled outages via early failure warning alerts, and allow a modern condition-based maintenance approach.”

Financial impact
It is vital for those responsible for the vibration monitoring and analysis program to establish a financial process that adequately shows senior management the impact the vibration program is having on the company’s profits.

A good monitoring system has the potential to save an organization considerable money as well as optimize equipment operation:

  • A company in the chemical industry reduced its maintenance expenditures from $9 million to $7 million and has maintained expenditures at $7 million for the past two years by instituting a vibration and inspection program. (Design Maintenance Systems Inc.)
  • A southern California paper mill was running at about 85 percent machine availability over the course of a year, largely due to unplanned outages. The mill implemented an aggressive predictive maintenance program using vibration data collectors as the key facilitator of the program. After 2 years, machine availability was up to 96 percent, and after an initial increase in bearing purchase, by the end of the second year purchases were down by two-thirds. (Ludeca Inc.)
  • A large bearing manufacturing plant diagnosed a pending bearing failure on the main air handling unit. Failure of this bearing would have shut down the air conditioning system in mid-summer resulting in several days’ lost production. The estimated savings was $350,000. (Technical Associates of Charlotte)
  • A paper company recently saved $3 million when a broken gear was identified in the gearbox of an outlet device. (Vibration Consultants, Inc.)
  • An 8000 hp gearbox was put into a maintenance turnaround schedule when a large thrust bearing defect was detected by vibration monitoring the month before the turnaround. Extensive damage and lost production were avoided. (Watson Engineering Inc.)
  • A petrochemical company achieved significant cost savings when it reduced unplanned maintenance. A reliability centered maintenance study which identified the appropriate monitoring frequency, methodology, and machine priorities was conducted. Savings achieved was estimated at $2.4 million per year. (SKF Reliability Systems)
  • A maintenance person at a wastewater treatment plant heard a strange noise from a blower bearing. A vibration survey confirmed that the inboard blower bearing was damaged with metal-to-metal contact. The noise was very subtle, but when compared to previous data from this same bearing, the trend was obvious and unmistakable. The bearing was changed and visual examination disclosed that one ball was severely spalled. The entire bearing would have operated for only a few more days. This analysis worked well because previous data from this bearing when it was in a known good condition was available. This analysis and repair avoided an unscheduled outage and possible fine of up to $10,000 per day for untreated sewage being discharged into the nearby river. (Machine Dynamics Inc.) MT

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6:00 am
May 1, 2005
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The Biggest Threat to Equipment Reliability: Skills Shortage

Our vocational-technical education infrastructure has been decimated over the past 30 years. The basic skills and knowledge for maintaining our industrial machinery and equipment are in critically short supply.

This shortage is having a significant affect on many businesses, large and small. Only those businesses that have nurtured their own skills development infrastructure are safe (“Vocational Classes Falling Out of Favor”).

The “perfect storm” is on the horizon. Massive retirements are on the way in the next 3-7 years as Baby Boomers begin retiring. Many large companies are now reporting a 30-50 percent retirement forecast from their maintenance technician ranks.

In the 1980s as the Baby Boomers’ parents retired, the jobs were filled with the most educated workforce of the century. The Baby Boomers were a product of a strong vocational-technical education system where vocational skills were not only in demand but among the highest paying careers. Industrial education programs populated our junior high and high schools, our technical schools and community colleges, and our colleges and universities during the 1960s and 1970s.

Then it happened—the “Baby Bust” generation; the Baby Boom generation in the 1970s had fewer children than our parents had after World War II. This group is known as “Generation X” and they have an outlook on life and careers that is significantly different than their parents and grandparents—not wrong but different. Much has been written on Generation X’s values and behaviors, too lengthy to explore in this column. What I will share is that their pursuit of vocational-technical education and training for careers in industry, for careers in industrial maintenance, has plummeted from the levels in their parents’ generation. This is part of the reason that vocational-technical programs have declined—lack of interest.

The perfect storm is on the horizon and most businesses are unprepared for the dangers that lie ahead. Where are the skilled maintenance and reliability technicians and the maintenance and reliability leaders going to come from?

Massive retirements will happen between now and 2012. The vocational-technical education infrastructure that supplied the skills and knowledge to fuel industry growth, expansion, and reliability since the 1970s is no longer there. And, over the past 15 years many companies have cut back their training expenditures and departments.

As maintenance and reliability professionals we know that jobs training is an essential ingredient of equipment reliability. Human error is one of the biggest causes of equipment problems. Many people who operate and maintain equipment unknowingly introduce, or ignore, failure modes due to the lack of proper training—basic skills as well as equipment-specific skills and knowledge. Employers also design jobs that promote a separation of skills and knowledge; “I operate it, you fix it.”

We can no longer afford to ignore the affect of untrained operators and maintainers on our equipment reliability. Manufacturing jobs will ultimately go to regions and countries where skills and knowledge exist to make these plants reliable, and financially viable. Employers who have strong focused job-related, equipment-specific skills development programs will thrive.

And, they will thrive not only because they have job-focused training but because they are appealing to the needs and interests of the Generation Xers inheriting the jobs of the retirees. The “Xers” want to learn. Learning new things that they can use is very important to them. They like challenges.

But they will also look for the easiest way, the path of least resistance—and that can be good for our businesses, too. They will change careers numerous times looking for a more rewarding, more satisfying job.

Today, our training programs must be fast and focused, highly efficient and effective. If your company is not training with this focused approach it may not survive the perfect storm.

Training today cannot be the long-drawn-out curriculum of the past. Apprenticeship programs must be accelerated and very, very job specific. Every employee who operates and maintains equipment must be trained in the equipment-specific requirements with a narrow foundation of the basic skills and knowledge.

But, as some employers have said: “What if we train them and they leave? We can’t afford to be the training company for the area.” Well, I have to counter with: “What if we don’t train them and they stay?”—Robert M. Williamson, Strategic Work Systems

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6:00 am
May 1, 2005
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Professional Development: Driving the Economic Engine

These days it seems that our economic engine is running just a bit ragged. Generally, it is performing fairly well, but we can’t seem to get the ultra-smooth, high-speed performance that we would like. It sputters a bit every now and then. Just when it looks like it is going to take off, it coughs or hiccups, and slows down before catching and starting back up again.

When one considers that technology and innovation have produced many significant improvements in recent years, the question is raised as to why our economic engine isn’t racing along. Why haven’t these improvements in components and machines and processes and systems caused our economic engine to accelerate to a smooth purring ride?

There are numerous issues influencing our economic engine—many real, many politic, and many mysterious. We could discuss capital formation problems, balance of trade politics, over-wary management, and so on. However, I want to focus on the part that professional development plays in this scenario. And more importantly—the role that professional development will play in the future performance of our economic engine.

As said above, our engine is running fairly well now, albeit with some fits and starts. While we are not at peak performance, we are certainly not in a crisis mode. Our industry is generally running well. I think this is true despite a real shortfall in professional development over the past few years.

Training budgets have been reduced as cost competition has driven companies to cut budgets. People resources also have been reduced due to tightened budgets. However, we have been blessed with a solid core of professionals throughout the ranks who carried on despite the reduced budgets and resources.

From crafts and technicians through engineers, supervisors, and managers, a tremendous wealth of knowledge and experience has generally seen us through the past few years despite limited resources. Although we have utilized them somewhat to our benefit, we probably have not taken full advantage of the recent innovations and other technical advances available to us.

Looking ahead, I see a crisis looming as our knowledgeable, experienced, and talented workforce leaves the workplace and is replaced by not-so-knowledgeable, much-less-experienced, and talented (yes, these new folks are talented) individuals. All the studies I see indicate that a massive migration of our workforce is going to happen over the next few years. Demographic studies indicate that more than 50 percent of the workforce can retire within the next few years. There is little question that our economic engine is going to be hit with some real changes and challenges.

While this experience migration “problem” (make that “challenge”) has many facets, and will require many necessary resolution approaches, I suggest that a major strategy is to embrace and drive professional development. From the crafts to the managers, the need for continuing professional development (or life-long learning) will become more and more critical.

Technology and innovation will continue to advance the science of how we do things. Globalization will continue to affect the way we operate our industries. Cultural and societal issues will continue to alter the way we manage our businesses. Our up-and-coming workforce will need to continuously develop and hone their skills—technical and managerial.

This calls for well-thought-out professional development strategies and plans. This calls for increased attention and commitment to professional development by individuals and organizations alike. This calls for utilization of new means of knowledge delivery (such as Internet delivery, interactive CDs, etc.). This calls for a development strategy that includes specific knowledge areas for each and all facets of the organization—crafts to managers.

Just as we keep our automobile engines in tune so we obtain the smooth, high-performance ride we crave, we need to pay attention to our economic engine to also receive the smooth, high-performance ride we crave. We wouldn’t take our new auto to the old, out-of-touch mechanic who worked on cars in the 1960s. We would insist on a mechanic who had been educated and trained on today’s engines. Should we do less for our economic engines—the ones that drive our livelihoods? MT

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