Reliability, Maintenance, Energy & Environment

New Industrial Economic Conditions and Motor Repair

2009-11-01T19:47:00.000-08:00

What an interesting world we live in. The good news is that we are watching businesses bouncing back after becoming leaner, although some didn’t stop at fat they went straight into muscle and bone. What does this mean for reliability and maintenance?

With only one spot in the second quarter of 2008 showing positive growth in the Gross Domestic Product (GDP) in the USA, and the 2008 into 2009 GDP sank into losses from -3% to more than -6%. This last quarter, in fact the last month of this last quarter, generated huge growth in GDP from a previous quarter of -0.7% to a positive of over 3.5%.

The GDP relates to business sales within the USA, meaning what businesses are producing here in the United States (including property). My contacts within industrial businesses have been reporting that production has been coming back very quickly, especially in heavy industry. While at the SMRP show in St. Louis a few weeks ago and the SMRP Chicagoland Chapter mini-conference three weeks ago many of the reliability and maintenance attendees had similar responses.

The challenge right now is that many companies retired off senior people and while bringing back many laid off workers they have not increased the number of employees to 2008 and prior levels. This means that most of the people that are back in place now have broader responsibilities and less support. One of the areas impacted the most is the R&M industry.

If we now couple this situation with suppliers and vendors reducing ready inventory and stock, there is the potential for bumpy roads ahead. Critical equipment failures and unplanned outages are already taking longer to return to full operation, critical maintenance personnel are working longer hours, and some equipment repair vendors… well, they are doing some strange things to equipment to get it back up and running.

I was seeing some of that before. Now, in my present position at Dreisilker, I am seeing the results of these other companies ‘short cutting’ in order to get things back out to our industry, or lengthy field repairs that aren’t necessary based upon a lack of experience by those repairmen. The result is reduced reliability through improper repairs because the correct parts are not readily available. I have even found that some companies have attempted to deliver materials that have already passed their allowable shelf lives by years! (Scary response… “The other shops aren’t returning this stuff!”).

Having had the perspective of supporting companies as an R&M consultant (something I still do for specific clients), and returning to the motor system field and shop repair industry, specific items have become glaringly apparent. The most significant one is that a significant number of my new competition (other repair facilities), with a few exceptions, are more worried that their ‘fixes’ make it through the warranty period and less that the motor is reliable and capable of performing at or above original capability. Even more interesting is that, while this was prevalent in the past, many are generating poor work and then making claims that failures are the fault of the owner and not the lack of insulation, poor connections, bad bearing fits, the use of glyptol on windings, and other short cuts that were taken.

Now, that does not include obvious warranty issues by end users. I have been observing many cases where poor applications, lubrication practices, contamination, not correcting the original fault, and similar issues, come back with warranty claims. Most of these relate either to poor maintenance practices or inexperience or improper application of the system that can be corrected easily. However, by making a warranty claim, corrective actions are not necessary.

It is important to remember that a motor makes an excellent, though expensive, fuse and that if you are not seeing an average 20 year life from a new machine or repair, then there is something causing it to not live as long as it should. While some of these may be related to workmanship, the vast majority are more related to the application or maintenance.

How do you determine which is which? How do you handle the increased workload? How do you figure out what the issues really are?

With things ramping up and little/limited support, there are ways to deal with this part, at least:

- Partner with your vendor. Determine your critical requirements. This helps both you and the vendor determine what to stock and have ready;
- Where possible commonize. For instance, if you have a large population of similar motors, use a common brand. This will mean that you will have lower stocking levels and an easier time having your vendor prepare ready stock;
- Have your vendor become familiar with your operations and people. That way they have the same level of urgency when things go wrong. Knowing a face will create a better response;
- Validate and visit your vendor. If they do not want you to see their facility, or they require significant advanced notice, that should be a red flag. In fact, during the tour, take note if anything ‘feels’ wrong because it might be. During one of my evaluations of a repair facility a few years ago, the repair shop was unaware of my background and tried to explain to me how all repair shops use flame throwers to strip windings from medium voltage motors. They literally turned parts of the laminations cherry red, destroying them, but used the damaged core anyways. In other cases, the repair facilities had neither the equipment, power or test equipment to perform any level of repair, in still others they would perform testing to a point where the motor failed (ie: 3500 Volts surge testing 460 Volt dirty and wet motors until the winding shorted on two stators);
- Develop a motor management program beyond just motor storage or repair versus replace, both methods that are components of a program and touted by vendors and organizations with specific agenda. A true motor management program is much larger than that (articles may be found at http://www.motordiagnostics.com in the archives). Feel free to contact me for more information on developing a program and what the impact can be (howard@motordoc.com);
- Set up service and delivery contracts with your vendors. These should have teeth in both directions, to ensure delivery by the vendor, but also so your management cannot easily back out and shut down a successful program.
- Maintain agreed-to new and repair specifications with reporting.
- Maintain and perform commissioning on new and repaired equipment. Commissioning is a series of tests and inspections performed to evaluate the condition of the equipment and to verify that the machine meets requirements and specifications.
- Ensure that testing and validation is performed before pulling equipment out for repair or replacement. An average of 15-20% of machines sent for repair or replace have nothing wrong with them in the first place and the problems actually reside elsewhere.

We will be discussing more in the near future.

In the meantime, stay alert as there are even more challenges and opportunities on the way. For instance, the new energy policy is almost in place and will have a significant impact on your repair versus replace decisions and how you work with your vendors. See the mini article “New Laws Concerning Motor Efficiency” later in this newsletter.

Questions? Contact me directly: howard@motordoc.com.

Sincerely,

Howard W Penrose, PhD, CMRP
The MotorDoc

Electrical Motor Diagnostics: 2nd Edition

2009-11-01T19:46:00.000-08:00

Sales dropped a little bit over the summer, but were still strong. Have increased significantly this month and orders are already being entered for November! I have to say, I have been pleasantly surprised by the feedback this award-winning textbook has received.

So, instead of just an advertisement, I will fill you in a little bit of the background of this book.

In 1998, while investigating motor testing methods at the University of Illinois at Chicago’s Energy Resources Center, as the Industrial Senior Research Engineer, I had asked for information on data interpretation of motor diagnostic technologies we were evaluating. The answers I received were… well, let’s just say, I understood people’s frustrations with the technologies. So, when I joined one of the companies, ALL-TEST Pro (a division of BJM submersible pumps), I started my research and performing training. In 2000 I released a training guide that I formatted and changed into the book “Motor Circuit Analysis,” which was released through SUCCESS by DESIGN Publishing in 2001, and was the book that launched SUCCESS by DESIGN. In 2003, I added “Motor Diagnostics,” which was the addendum to “Motor Circuit Analysis.” But I wasn’t satisfied, there were still some holes.

I continued research in the technologies based upon field experience and worked closely with the UAW-GM predictive maintenance folks to come up with material that was not intimidating to a novice with or without electrical or test equipment experience, while providing a ready reference and challenge for those with experience. The result was “Electrical Motor Diagnostics: 2nd Edition,” which included significant research in a number of areas and tables, such as rotor bars and stator slots, which are badly needed for accurate analysis.

I also felt it was necessary to address other technologies, such as simple resistance, current and voltage readings and how they could be used to analyze machines, and the limitations of the different technologies. Other areas included: Time to Failure Estimation™, a concept that was recently published in the IEEE (Institute of Electrical and Electronics Engineers, Inc.) Electrical Insulation Magazine (July/August 2009, Vol 25, No. 4); and, an overview of setting up a motor diagnostics program.

Not only has the book won a finalist position in the Foreword Book Awards, but I constantly receive responses back from readers on what it has done for them. I have also started receiving requests for teachers guides, which is outstanding. In fact, for 2010, we are going to have a complete course built around the book designed so that your trainers can purchase an Electrical Motor Diagnostics training system. I am quite excited about it.

For details on “Electrical Motor Diagnostics: 2nd Edition,” go to: http://www.motordoc.com/detailEMD.htm

Electrical Motor Diagnostics is available from our distributor, any online bookstore, and the ReliabilityWeb bookstore through MROZone (http://books.mro-zone.com/category_s/63.htm and normally in stock) was featured at the SMRP conference MROZone bookstore and will be available at Solutions 2.0.

SMRP 2009 Show Report

2009-11-01T19:45:00.001-08:00

With so many conferences and shows with extremely low attendance or not happening at all, it was a pleasant experience to attend SMRP in St. Louis this year. The estimate I was given was about 650 attendees, which was plenty for some really outstanding presentations from practitioners.

While the venue was not the best for good booth traffic, such elements as the tour of the arch and banquets were fantastic. There were other significant discussions related to the future of reliability and maintenance, and great feedback as to the state of our industry and present productivity within the USA and abroad.

As the Treasurer of the Chicagoland chapter of SMRP, I was asked to attend the chapter leadership meetings which started after lunch the Sunday before the conference started. Workshops started on the Monday as well as CMRP exams. I had the chance to shadow two of the exams so that I could become qualified to give the exams for the SMRP Chicagoland chapter during our meeting on February 23, 2009, which will be a tour of Dreisilker Glen Ellyn and a discussion of how to set up motor repair specifications.

Unfortunately, I did not take too many pictures of this trip as I was having way too much fun!!

New Laws Concerning Motor Efficiency

2009-11-01T19:43:00.000-08:00

Things are changing, again, and will have a significant impact on retrofit and repair versus replace decisions in the USA soon.

The original Energy Policy Act decision related to electric motor efficiency was included in EPAct 92. This was concurrent with other global energy policies that looked at general purpose electric motors and set efficiency levels. In the United States, the Act was passed on October 24, 1992, and required that manufacturers of general purpose NEMA frame standard efficient motors from: 1 to 250 horsepower; 1200, 1800 and 3600 RPM; and, foot-mounted meet NEMA energy efficiency tables by October 24, 1997. The program was very successful.

In 2007, the Energy Independence and Securities Act took this a step further, expanding the original requirements to meet premium efficiency tables, including C-face and D-flange motors after December 19, 2010. This means that manufacturers can only manufacture energy efficient motors until that date, they can be purchased any time after. The Act also expands the motors that must meet NEMA energy efficiency tables for all motors up to 600 Volts, including motors up to 500 horsepower, close-coupled pump motors, vertical hollow shaft, footless, firepump, u-frame, 8 pole and design C motors. Such a program is going to have significant impact. For instance, U-frame motors are still built that meet the original 1968 efficiency standards which are referred to as automotive duty u-frame. The new efficiency standards will allow them to be built. However, the efficiency requirements will be higher.

Before the August, 2009, recess, the Senate has proposed Tax Bill S. 1639, the ‘Expanding Industrial Energy Efficiency Incentives Act,’ that provides a tax credit of $125 per hp for the substitution of advanced motor systems with adjustable speed capabilities. The purpose is to give OEM manufacturers incentives to design machines using more efficient systems.

To top this off, the Incentives Act has a cash for clunkers program for electric motors referred to as ‘crush for credit.’ The purpose is to incentivise motor owners to make premium efficiency choices over repairing older motors. In this program there must be evidence that an existing motor is replaced and disposed of as part of a repair or retrofit. If this is included in the Act, it is presently proposed at $25 per HP to users who purchase new premium efficiency motors. To assist repair shops that are expected to take a huge hit, there will be a $5 per HP disposal credit, in addition to any scrap value, with evidence of its disposal. This program will cover both <600 Volt motors and some medium (up to 6kV) motors.

The impact on the motor repair industry may be significant as a majority of shops handle motors well under 500hp. The larger, broader-based repair facilities will fare much better.

As always we will keep you informed!!

IEEE DEIS Web Overview

2009-11-01T19:37:00.000-08:00

The IEEE DEIS Web has been doing very well (http://www.ieee.org/go/deis/).

The site contains a Wiki, forum, abstracts and links to more abstracts on insulation systems, educational videos recaptured from presentations long gone by, and much more!!

We are setting up pre-college information for teachers and students to interest them in engineering and related careers. If you know of any curriculae, programs, software or links that relate to insulation systems for education, please forward them to me: hpenrose@ieee.org.

As an incentive to consider joining or participating in the IEEE DEIS Web, including advertising, we have made the “A Brief History of Insulation Systems” educational video available for all viewers. The link is: http://ewh.ieee.org/soc/deis/education/video-detail/education/a-brief-history-of-development-in-electrical-insulation.html This video will be available through November, 2009.

If you wish to be a blogger you may also apply to me at the email address above. If you have a rotating machinery audience (motors, generators, components or insulation systems), please consider advertising by contacting me for pricing and information at hpenrose@ieee.org.

MotorDoc on Leadership

2009-10-11T18:09:00.001-07:00

Leadership requires experience and knowledge, yes. However, contrary to what is read in a great many books, there is an inherent ability that comes with it. Not everyone is cut out for real leadership and not everyone will have the same or similar style, if they have the propensity to be a leader. In fact, leadership ability in one area does not guaranty that same person will be successful or unsuccessful elsewhere.

The objective of a good leader is to have the personality of a coach, regardless of technical ability. Recognize the strengths and weaknesses of those they are responsible for and utilize those resources. It also requires the knack of being able to challenge those resources to excel within their abilities.

Just because someone is either in a position of authority or the lowest person on the totem pole, or the person of greatest or least technical ability does not mean that leadership is important or unimportant. A boss, or manager, will direct, order or dictate direction and will remain rigid. A leader will guide and support.

An inexperienced leader will not always be aware that they are a leader, but others may. In this there is danger as they may find that they are being manipulated by coworkers or others that want to use their influence. This is where the leader that is going to excel will find that the comments from one or two individuals from a group do not reflect the actual needs of the entire group.

This is important. A good, experienced leader will maintain a global perspective on the areas that influence himself and his resources (gender non-specific, if you are going to comment). While a great many of the details can be learned, the personality and ability to see the bigger picture and how all of the pieces fit in is required.

Don’t get me wrong, there are varying degrees of leadership ability in everyone, and experience brings those abilities and limits to light. But there is that component of a true leader referred to as charisma, the ability of people to naturally lead or attract others, that must be present. That component is fully based on the personality of the individual.

In fact, even where charisma is concerned, the ability must fit into the situation. For instance, a natural military leader, business leader or political leader may not fare well elsewhere. Often, a leader will rise to the top in a particular situation and other times will shine even as a follower.

With all of the books, rules, instructions, courses, etc. that exist on the topic of leadership, you would think that there would be one ‘silver bullet.’ However, you will notice that the books do not relate and there are a great many schools of thought on what makes a leader. The danger is when one tries to emulate a particular leadership style, especially if it does not match their personality, the attempt become stressful to all involved with the individual eventually falling back on their old habits.

Therein lays the purview of the true leader and coach. One who accepts who they are and how their personality and charisma works with others. The habits for an individual can be changed. Changing personality and charisma traits are far more difficult, if not impossible, without completely changing the person.

Have I been saying that a natural leader should not study other styles and methods? No. A true professional, leader or otherwise, should be constantly looking for ways to improve.

Leadership also has another effect. A good leader will gather and attract like-minded individuals around them. A truly outstanding leader will surround themselves with people that have strengths where they are weak and will begin to fit a puzzle together. But not opposite; contrary to popular thinking, opposites do not attract or bring positive outcomes.

Can someone who is unsure of themselves or who lacks confidence be a leader? Absolutely! Often, where you have strong intellect or wisdom, that person, or persons, are constantly questioning themselves. While this may show as a lack of confidence, it can simply be self-exploration or seeking. In fact, not all leadership requires decisiveness, especially when coaching.

Decisive leaders will also constantly question themselves. This is one of the more dangerous types of leadership where competence is extremely important. And, when things do go wrong, and they will, the decisive leader must be able to go back and review the situation. This is often considered the more powerful type for leading groups in that people will have a tendency to approach this person for advice easier.

Is leadership required to be successful? Is everyone a closet leader with most just holding back? No! For whatever reason, people think that they must be a leader because society says they must.

For instance, I have met some truly competent people who do not aspire to going beyond what they are doing. In today’s society and management styles this is somehow a crime. In reality, a true leader will recognize these people and help them excel where they are while being prepared should something trigger that person to want to change. People and organizations are dynamic and a leader needs to be fluid.

What it comes down to is that my style of leadership may be significantly different than yours. Which one is right?

Press Release: McHenry Industrial Program Gives Grant to Dreisilker

2009-10-11T18:04:00.001-07:00

NEWS RELEASE
FOR IMMEDIATE RELEASE CONTACT: Jim Allen, Director of Manufacturing
DATELINE: Monday, October 12, 2009

McHenry County EDC’s BAIC Program Funds New Product Development at Dreisilker Electric Motors

McHenry, IL Monday, October 12, 2009 ----- McHenry County EDC’s Business Accelerator for Innovation and Collaboration recently awarded a grant to assist Dreisilker Electric Motors, Inc. develop a new line of electric motors for high temperature environments. These water-cooled and water-jacketed motors are being designed from scratch. “Not only will these motors be able to withstand harsh, high temperature environments, but they are also roughly half the physical size of competitive motors.” said Dr. Howard Penrose, Vice President, Repair Services and Engineering and product designer. Leo Dreisilker, President of Dreisilker Electric Motors added “This comes at a good time to help broaden our product offerings to our customer base.” The new product line is expected to generate additional sales and create jobs and has completed prototype and engineering.

Dreisilker Electric Motors, located in McHenry, IL and headquartered in Glen Ellyn, IL, manufactures
special electric motors ranging in size from fractional horsepower up to 600 HP, repair services to over 10,000 horsepower and field services globally (http://www.dreisilker.com). The present product line available since 1993 includes precision 5700 RPM motors to 455hp and high temperature motors to 600hp. They have six other locations in the Chicago area to Atlanta, GA. Dreisilker Electric Motors will be participating in the 3rd Annual McHenry County EDC Manufacturing Matchmaking Event Oct. 27.

Photo: (second from right) Jim Allen, Director-BAIC, presents check to Louine Sternickle, Sourcing Specialist, Dreisilker Electric Motors. Also in attendance from Dreisilker Electric Motors: (far left) Rick Sawisch, Service Manager, (second from right) Leo Dreisilker, President, and (far right) Dr. Howard Penrose, Vice President, Repair Services and Engineering. Photo courtesy of Dr. Penrose. The motor represented in the picture is another Dreisilker water cooled design.

BAIC is an SBA funded initiative secured through the efforts McHenry County EDC, McHenry County College and Illinois Congressman Don Manzullo. BAIC, the Business Accelerator for Innovation and Collaboration was established to focus on the needs of over 600 manufacturers in McHenry County, providing business assistance and consultation, free of charge. Utilizing a significant network of relationships, BAIC provides a vital link to the state, federal and private resources available to manufacturers with a focus on creating jobs, ideas & revenue. For more information contact McHenry County EDC at 815.363.0444, email manufacturing@mcedc.com or visit (www.illinoismanufacturing.net)

The McHenry County EDC is a non-profit private-public business advocacy group comprised of business and industry investors from throughout the county. Its mission is to encourage and develop the economic health of McHenry County through the retention, expansion and attraction of commerce and industry which is conducive to an optimal quality of life for its citizens. A non-governmental organization, the McHenry County EDC seeks to work with local, county, state and federal legislators to foster, enhance and improve the economic vitality of McHenry County.

Impact of Electrical Motor Diagnostics on Motor Repair and Services

2009-10-11T17:59:00.000-07:00

When I entered into the Electrical Motor Diagnostics (EMD) industry in 1999 after studying it at the University of Illinois at Chicago’s Energy Resources Center from 1997 and performing other motor field and shop testing from 1984, I noticed something particularly interesting: a great many repair shops resisted their customers performing any type of testing. Why would this be? On the other hand, many motor repair facilities that performed field services, and other types of field service companies, quickly embraced the technologies and provided services.

Immediately upon entering into the instrumentation side I had my first experiences. On one of my first sales presentations I was taken into a Ford plant where we noticed significant unbalances in random motors from a specific repair facility. When asked, the maintenance professional noted that these motors would be identified as having single phased by the repair shop and the tradesmen were being blamed. However, the maintenance staff and managers could not find any reason for the failures. So, fingers were pointed and the repair facility continued repairing their motors. Our forensic analysis identified that the repair shop, when they would run out of wire during the repair process, would splice conductors and continue. In many cases, if they did not have the right wire size, they would splice in two conductors two sizes smaller. This would result in roughly the same simple resistance, but would dramatically change the impedance of the circuit and cause the parallel circuits to act as a transformer, heating up the associated coils and often acting similarly to a short circuit.

In another case, an end user became suspicious of their repaired motors. Data was taken before and after a repair. As it turns out, the repair shop was altering the winding design and conductor sizes so that they could turn the repair around further. The decision was solely for the convenience of the repair shop and absolutely not of benefit to the end user.

An Electrical Apparatus Service Association (EASA) survey identified that 81% of repair shops ADMIT to altering the windings through the repair process of which 73% ADMIT to doing it for their own convenience. Less than half of repair shops across all sizes perform any type of testing on the motor from the time it comes in until the time it leaves. While customers provide repair specifications, the results of my field surveys and feedback, most repair shops outright ignore the customer specifications because they know the customer will never visit the repair shop or confirm that the specifications are being followed.

While I was in the EMD vendor industry, during a number of sales presentations, customers would either ask their repair shop to evaluate the technology or their direct opinion. Most of the time the repair shop would immediately dismiss the technology. The times I would have the opportunities to get the repair shops to respond, the statement was always the same, “we don’t want our customers testing our repairs.”

Hmmmm… Interesting response, isn’t it? To be perfectly blunt, the only other times I have run into negative statements related to EMD technology: a) the person or organization has never put the technology into action or had never seen it used; b) the individual cannot grasp the technology and voices a loud negative opinion; c) competing technologies; and, d) rarely an actual user who may have misinterpreted data or misunderstood its capabilities. Those who have bought into the technology have had great success with it.

So, back to the original question:

First, an emerging technology represents an unknown. Such things can invoke strong negative reactions from entrenched technologies and fear of the unknown by others. This includes motor repair shops especially, as knowledge has been disappearing. That is right, a great many, and growing, number of repair facilities actually do not understand electric motors, their components, and, more importantly, applications. The level of actual knowledge within the industry has been dropping at a quickening pace. So, for a customer to suddenly start utilizing a technology they do not understand, when the repair facility is asked a question they cannot answer, they are no longer the experts. Not a good position to be in should you have positioned yourself as the expert.

Second, the repair facility may be cutting corners and they do not want their customers to discover it. With over 81% of repair shops modifying motors from the original design this is a serious issue. As a result, I pushed the concept of commissioning repaired motors in order to capture such issues immediately.

So far as the positive impact on the industry:

1) Honest repair shops will often want their customers to evaluate/commission repairs. It sets them apart and poor competition stands out very quickly. Additionally, issues are brought out immediately, providing an opportunity for the repair shop to step up to the plate and show what they are made of.
2) The repair shop or field service group will often add motor diagnostics as a service. With the demand for these technologies increasing and the level of knowledge and training required, this is a very lucrative opportunity.
3) Repair facilities may use these technologies internally, providing confidence and the ability to communicate with customers who use the same, or similar, technologies.,

It is important for the repair and service industries to embrace newer technologies and challenge themselves. With customers operating with shoestring budgets and limited personnel, services and information can be provided that should be considered invaluable.

A few things to consider as benefits of a commissioning and predictive maintenance program:

1) Commissioning tests can help in troubleshooting equipment later. One powerful ability of some testing methods that use low voltage impedance measurements is the ability to identify overheated or contaminated windings. At the transition point where winding shorts occur in these conditions, the impedance readings have already dropped. If impedance based test results exist for a motor that has been commissioned, these conditions are identified with the impedance values dropping.
2) If motor circuit analysis tests, including resistance, impedance, inductance, and others (reference IEEE Std 1415-2006), are used for condition based maintenance or previous commissioning, they can be compared to a motor returning from repair. This can be important if you are unable to verify that your specifications or standard industry practices are being applied. If readings have changed, it is an indicator that the windings have been changed from the original and the motor will not perform as designed.
3) If you are using repair specifications you must verify that the repair shop is actually following them. This can be done with onsite inspections or requiring specific reports, as found and final reports (often referred to as root cause analysis in the motor repair industry which is dramatically different than what is considered root cause analysis in the reliability industry), digital photos, etc. If you do not already have a specification in place, please feel free to contact us for a quotation (howard@motordoc.com) on motor repair specification development or recommendations.

For more information on starting a program, or other related questions, please feel free to contact me directly at howard@motordoc.com

SMRP Chicago Chapter October 15 2009 Meeting

2009-09-28T19:44:00.000-07:00

October 15, 2009, SMRP Chicago Chapter Meeting.

SMRPMeet.pdf

From the MotorDoc: Something Lite (Reflection)

2009-09-20T10:15:00.000-07:00

Once in a while I like to consider something philosophical. Following is a piece I wrote to break through writer’s block a few weeks ago while working on a project for my writers’ group. Yes, it does even happen to me.

REFLECTION

Howard W Penrose, Ph.D., CMRP

I sit, trying to think what to write as I gaze across the pond outside my window. The two fountains at either end spray high into the air in the sunlight with only occasional clouds obscuring the rainbow that fades in and out from the nearest one. The colors deepen and lighten then fade out completely, then come back again.

The ripples move out from each fountain in a circle, rebound against the irregular edges of the pond, then back in again. The chaos collides with the chaos from the second fountain such that a regular pattern forms on top of the pond. Every once in a while a breeze comes up changing the pattern, causing the wavelets to shimmer and dance.

Reflections of the surrounding homes dance within the pattern. Shapes without solid edges until you look up slightly. A flock of birds fly from roof to roof in regular intervals, land on another roof, take off again and swoop over the pond and onto another roof. It is almost clockwork. They find shade, huddle under an overhang, then start their dance all over again.

The branches of the evergreens around the pond sway in the breeze. It is cool, but not too cool, fall-like weather in August. The pinecones dance as if they are bells. I hear the tinkle of a wind chime and the bark of a small dog.

The birds swoop by my window. I am starting to recognize the lead bird, it seems to be the same one, waiting for his troops to land, then ordering them all up and off again. Their flight is reflected as a new pattern of light upon the ripples in the pond. This time, one stays behind and, now, flies to a different rooftop. Will the others follow?

I gaze back down towards the pond. All of those peaks and valleys colliding with each other, driven, yet responding if only to cancel each other out or change direction, even slightly. As if they reflect personal interactions. Lives begun, changed, extinguished, outside forces reflecting upon them and others as they change direction.

As we pass through life, we are reflections of our experiences. We are ripples, rainbows, wind and blurred mirrors of our surroundings. We travel and change each other in different ways, affecting those around us and others in turn. Sometimes we add, sometimes take away, sometimes cancel. We each live our peaks and valleys as we progress, sometimes we shine and sparkle, sometimes we fade.

But we are all reflections of each other.

I hope you enjoyed. Lots of information in this newsletter so keep on reading!

Sincerely,
Howard W Penrose, Ph.D., CMRP

Find me on Twitter (http://twitter.com/motordoc and http://twitter.com/IEEE_DEIS), Facebook.com and LinkedIn.com

A Review of Motor Management

2009-09-20T10:14:00.000-07:00

A variety of concepts related to the term ‘motor management’ have been presented within industry since the 1990’s. Many of these programs are actually ‘energy-efficient electric motor retrofit or repair/replace’ ideas that actually only make up a small portion of the overall industrial opportunities when properly managing electric motor systems. Normally, such things as preventive and condition-based maintenance and other motor-system opportunities are left out of the program with a very narrow view of the overall system. While it is important to view energy and environment when making electric motor decisions, it is more important to focus on the reliability, life-cycle and business-related considerations for overall corporate success.

Presently, over 20% of the USA Gross Domestic Product (GDP) is invested in maintenance programs with over half of that amount due to improper maintenance. An additional $2.5 Trillion in business opportunity was lost as a direct impact of poor maintenance practices. A majority of the systems affected are part of plant electric motor systems.

For more information, see the article “The Concept of Motor-System Maintenance and Management,” and related motor management articles in our articles archive: http://www.motordiagnostics.com.

What Infrared Can Tell You About Your Electric Motor

2009-09-20T10:12:00.000-07:00

Infrared can be used to thermally evaluate equipment. However, it requires direct contact of objects and line of sight for the system to work. In many electric motors, there are ribs between the frame and stator core which acts as an air thermal insulator. The result is that the surface temperature of the motor may be radically different than the actual winding temperature. At the same time, bearing inner and outer races are in direct contact with the bearing housings and shaft providing more accurate temperatures for evaluation and trending.

So far as the overall temperatures of the electric motor, there are a few temperatures that make up an electric motor’s operating temperature:

- Ambient Temperature: environmental temperature immediately around the motor. This limit, often 40C, is a limit for heat transfer from the motor.

- Temperature Rise: generated by the losses of the motor during operation and is directly related to the load of the motor. Basically, if the load rises, the temperature increases.

- Total Temperature/Operating Temperature: the combination of the ambient temperature and rise. As described, this value will vary with load.

The temperature limits for an electric motor are based upon the insulation class of the motor and bearing grease limits for the associated components. For instance:

- Class A = 105C – based upon the original oil and paper or tar and paper insulation systems

- Class B = 130C – commonly found in older standard efficient electric motors

- Class F = 155C – commonly found in energy and premium efficient electric motors

- Class H = 180C – often relates to insulation systems for high temp applications or motor repair

- Class N = 200C – high temperature applications

For motors that have service factors of 1.0, the allowable total temperature is the insulation class temperature minus 10C. For motors that have service factors of 1.15, or better, the allowable total temperature is the insulation class temperature. For example, if a motor has a Class F insulation system, a 1.0 service factor has a temperature limit of 145C and a 1.15 service factor has a temperature limit of 155C.

The temperature limits are not reflected on the surface/skin of the electric motor, as some believe, because of air gaps and the design of an electric motor to eliminate the heat generated by the losses of the motor. Different designs will generate different levels of losses and heat dissipation. The temperature limits, instead, related directly to the winding temperature of the motor. This requires either a direct line of sight of the motor windings or the motor core.

Thermal imaging has been used to identify specific point losses on an electric motor, with limited results. For instance, you have to know the loading of the motor at the time of test. Plus, in the case of totally enclosed fan cooled, or totally enclosed blower cooled, the skin temperature of the motor will vary from the fan end towards the drive end of the motor. This does allow the thermographer to identify cooling issues in these types of motors (ie: damaged fan or plugged cooling).

So, what can infrared tell us about our electric motors?

- For motors of constant load they can be used to identify ‘differences.’ However, significant temperature increases identify systems that have already failed;

- Bearing temperature by looking at the shaft and housing temperatures;

- Cooling issues;

- Severe faults;

- Can be used to determine where thermal issues are from.

In many cases, the use of just infrared technology can take significant time to evaluate or identify what is wrong and will often not provide enough detail to show how out of tolerance something is. For instance, thermal imaging may identify misalignment. However, what is good or bad? How out of tolerance is the alignment? For that you would have to perform an alignment check. Meaning – the right tool for the right job.

Does this make thermal imaging the wrong tool? No. It may be used as a system of scanning groups of equipment in order to identify gross defects which may be addressed through the application of the proper technology or inspection.

Consideration for Electrical Signature Analysis in Variable Frequency Drives

2009-09-20T10:09:00.000-07:00

For some reason, variable frequency drive driven equipment seems to carry a mystique for analysis. In truth, it just requires the user of diagnostic technologies the ability to expand the way they think when they look at data. Fault signatures and peaks are just the same as a standard motor, with the following exceptions:

- Currents should be balanced within 7% because voltage must be balanced on the output of the drive. If there are voltage related unbalances, then the drive should be evaluated, if a current unbalance exists without a voltage unbalance, then the motor and connections should be evaluated. It should be noted that the allowable current unbalance is meant for certain winding designs that are common in ‘smaller’ (less than 250hp) motors that have ‘concentric’ windings versus larger machines that have ‘lap’ windings.

- Expect very high harmonic content because of the type of voltage and current waveforms that exist. In most cases, this requires the application of filters or shaft brushes to avoid shaft currents.

- The line frequency and speeds will vary from test to test or during the same test. Evaluating and confirming the line frequency and operating speed, either through the signature or separate readings, is important as virtually all faults are related to one or the other. It is also important for when performing trending readings.

- You have to look past the electrical ‘noise’ that will exist in higher frequency data analysis to identify the issues in the system. This means knowing the fault signatures that you are looking for or practiced pattern analysis (covered in Electrical Motor Diagnostics: 2nd Edition).

There are other considerations that we will cover in future newsletters.

On Change Management

2009-09-09T06:35:00.000-07:00

One of my favorite subjects is change management. There is just something about it that can be considered both a powerful tool and a terrific weapon against competition. In either case, it must be remembered that both weapons and tools can be turned on the wielder, should either be misapplied.

Change invokes fear in many people, even when it is to their benefit or does not affect them at all. Unfortunately, many see the fact that there is fear, protectionism, or negative reaction as a positive response that change is occurring. This is a bad indicator for progress or positive change.

The use of change as a tool requires the architect of that change to have specific goals or series of goals in mind with each change being an effective step towards those goals. The application of change without goals or proper planning is simply chaos that cannot be managed in a process type environment. The result can be a reduction in quality, timeliness, and lost opportunities such as missing issues within a system. Solid processes in production or service in industry, manufacturing and personal environments allow for specific measurements, such as key performance indicators, and a methodology to identify areas for improvement. Once thought of as a way to 'keep people on their toes,' chaotic environments do not allow for proper measurement systems and generate environments of high stress.

So, how do you identify and manage change in a positive manner?

Often the 'change agent,' or manager/consultant brought in to make the change finds a potentially overwhelming situation. There may be a lack of documented processes, the documentation does not meet the processes, or the whole system may be in complete chaos. There are choices that must be made: where to start? How much to take on? Sudden and abrupt change? Or, slow and steady?

Based upon the agent's experience, there may be some quick changes that can be made to improve the situation and make it manageable. The next step is to gather information and records as well as observing the processes and business environment. While doing this, the agent must also determine the goals of the organization, not just by what is written, but by the actions of the leadership – actions speak louder than words, written or spoken.

Once that direction is determined and the agent has the 'lay of the land,' then the real work begins. First, determine what goals are going to be set in near, mid and long-term (immediate, months and years). Next, what measures can be used to determine if the goals are being met and the associated gap? Before getting down to the real changes, gage the acceptance of the company to change by implementing a relatively minor change in policy or process that impacts a large segment of the organization. This assists in determining: 1) where resistance will come from in the larger picture; 2) who will be of value during the change process; 3) will leadership support the programs? All of which will help determine the time-line and if a change management program is feasible in the company.

Do not take on everything at once! Select a specific program or project and maintain a steady pressure on it until it begins to operate on its own. Basically, prepare the next project once the first one is self-sustaining. Otherwise, the implemented changes will slip backwards.

Beware the idea of coming in, as a change agent, and laying about with unplanned or reductionist changes to the system, as is a common practice when trying to show immediate progress. You must also communicate the changes, support the personnel implementing the changes, help some workers through the challenges of dealing with change, and deal fairly, but aggressively, with those who deliberately attempt to prevent the change, especially those who undermine the effort in order to support hidden agenda that are contrary to the goals of the company.

Personally, I have never understood the motivation for that last statement, but have seen it often enough to be concerned. Why would personnel (leadership or otherwise) want to harm the company or organization that supports them? But it happens, and those persons should be eliminated from an organization quickly! They tend to be an insidious poison that eats away profits and effort through personal politics or undermining efforts through rumors and counter-productive activities.

When we go back and review those programs that have been successful within industry, and those companies that are highly profitable and in demand, a common thread exists: they each have solid, but flexible, processes that support their programs. For instance, you may have heard of the 'Toyota Way,' and the time when Japan was dominating over USA quality and cost. Those successful programs were not implemented in an environment of chaos. They were implemented during times of tightly controlled and measured processes and attention to detail. The same goes for companies like Nucor Steel and others who not only took charge of their processes but also identified the importance of the most flexible systems: people.

In this there is a fine line. You need to support the people who implement and move within the processes and changes that need to be made. At the same time, you need to tightly control the processes, set goals and policies, and determine the measurements those personnel must work within. Lean too far with flexibility without constraints in one direction and you have chaos. Too far the other direction, you have autocracy with the organization paralyzed during times when decisions must be made.

What are the rewards? A company that has clear processes and flexibility, or culture of change, can adjust to virtually any business climate. They can also prevent the competition from latching on to any specific issue, providing a solid defense in the marketplace, while showing a tremendous offense by being able to respond to customers easily while the customer knows exactly what to expect. With solid measurements and consistent processes, quality and time issues can be quickly identified and addressed.

Seeing as business is civilized warfare (ok, sometimes civilized) the concept can be re-enforced by looking at such conditions. If you have a force of structured, disciplined, process driven, fighters, such as the Romans at the height of the Roman Empire, against an angry mob, who is going to win? The group that knows exactly what to expect of themselves? Or, the chaotic mess?

Know yourself and win 50% of engagements, know your enemy and win 50%, know yourself and your enemy and win virtually every battle.

As process and change begin to occur towards the goals that you have set for your organization, it is important to keep a constant level of energy aimed at the systems put in place. If a system is changed and then abandoned, as with all systems of order, they will tend back towards chaos. Basically, any orderly system is subject to entropy. To properly maintain your system, buy-in is important across all levels within the organization.

So, as we come upon a new age of prosperity, which are you? Does your organization act as an angry mob? Or are you organized, disciplined, and flexible?

The future is here. Are you ready?

Electric Motor Repair Half Life

2009-08-03T19:50:00.002-07:00

A term that has become more and more common in the motor repair industry is ‘electric motor repair half-life,’ which refers to the concept that repaired electric motors will only half as long as the original new motors. The concept brings a lot into consideration for a company concerned with equipment reliability. If the idea of a repair half-life is true, what is the impact of our repair versus replace decisions?

In the 2006 Advanced Energy study and report, “Achieving More with Less: Efficiency and Economics of Motor Decision Tools,” on page 40, a Weherhaeuser report on electric motor reliability is discussed with the following conclusions:

- 50% of new motors fail in seven years; and,
- 50% of rewinds last only 3.5 years.

This would seem to support the notion of a repair half-life. It also identifies that not all facilities enjoy the 20 to 30 year average motor life discussed in numerous articles and research papers. Usually, the failures will relate to improper application, contamination, misuse, or other outside influences placing stresses on the electrical, mechanical or both types of systems within the machine. As I have mentioned in the past, an electric motor makes an excellent, but expensive, fuse.

What makes a repaired motor, or some repaired motors, more susceptible to these issues than a new electric motor while others are not?

In the 1995 Bonneville Power Administration (US Department of Energy) report, “Industrial Electric Motor Repair in the United States,” it is outlined that: 80 percent of repair facilities change winding configuration, often without understanding the potential consequences of the changes; 41% of repair shops reported burn-out temperatures in excess of 750 degrees F; and, “proper testing, which may include tests for insulation integrity, winding resistance, vibration, rotor balance, and core loss is essential for all repairs. It appears that only insulation testing is done routinely.” Comprehensive, or even basic testing, is performed by fewer than half of the motor repair facilities.

It has been found through numerous studies, including the 1995 Canadian Electrical Association (CEA 9205 U 984), “Evaluation of Electric Motor Repair Procedures Guidebook,” that proper and improved processes will provide similar, or improved, reliability as new. A combination of the studies and results can be found in the 1997 IEEE Electrical Insulation Magazine Article, “Anatomy of and Energy Efficient Electric Motor Rewind,” (Penrose) and other papers that can be found at http://www.motordiagnostics.com/presentations.htm.

Alternative motor repair processes, such as low temperature coil removal processes, special machining processes, automated coil winding, trickle varnishing systems, and quality control systems is outlined in the 1995 IEEE Electrical Insulation Conference paper, “Time Savings and Energy Efficiency through Alternate Electric Motor Rewind Methods.” (Penrose, H. W. and Bauer, B.) This paper outlines the only process that can provide a true 24 hour turnaround for motors under 400 horsepower without having to make shortcuts. The result is energy efficiency, reliability, and a turnaround time that will allow for rapidly returning a facility to operation for critical machines.

Some of the issues that can impact the life of an insulation system, including how to calculate the expected life of an insulation system, can be found in R. L. Wall’s IEEE DEIS Web video, “Fundamentals of Motor Insulation for Repair Shops: Part 3,” http://ewh.ieee.org/soc/deis/education/video-detail/education/fundamentals-of-motor-insulation-for-repair-shops-part-3.html.

If you have questions or comments on this topic, please email me at hpenrose@dreisilker.com.

Follow the MotorDoc on Twitter: http://twitter.com/motordoc or find me on LinkedIn: http://www.linkedin.com/in/motordoc

Sincerely,

Dr. Howard W Penrose, Ph.D., CMRP
IEEE DEIS Web Editor in Chief (http://ewh.ieee.org/soc/deis)

Motor Repair Tours

2009-08-03T19:50:00.001-07:00

Electric motors of all types cut across all industries and applications. However, most reliability and maintenance professionals have limited exposure to electric motor theory and electric motor repair. After having returned to Dreisilker Electric Motors, Inc., with our main repair shop in Glen Ellyn, Illinois (and second facility in McHenry, Illinois) along with an additional six storefront branches throughout the Midwest and Atlanta, Georgia (see http://www.dreisilker.com), we have an opportunity to educate you.

If you are a commercial or industrial/manufacturing end-user, specify electric motor repair or motor management programs, feel free to contact us for a tour of the Dreisilker Glen Ellyn, Illinois, facility. You can contact me direct at 630-469-7510 ext. 320 or email hpenrose@dreisilker.com. Trade schools, colleges and university class tours are available.

It is our goal to help you understand our industry.

Dr. Penrose Wins 2008 UAW-GM People Make Quality Happen Award

2009-08-03T19:48:00.000-07:00

After winning the 2005, 2006, and 2007 UAW-GM People Make Quality Happen Awards for energy, environment, and reliability programs throughout General Motors as part of the Joint Task Team for Construction and Maintenance, Dr. Penrose has been awarded the 2008 UAW-GM People Make Quality Happen Award for reliability and energy programs in 2008. Programs have included reliability and maintenance task and program best practices for a reduced and changing workforce, joint US Dept of Energy/GM/UAW programs for energy and environment improvements, and the development of the GM Motor Management program.

IEEE Dielectrics and Electrical Insulation Society Web Educational Videos

2009-08-03T19:47:00.000-07:00

We continue to convert IEEE videos for IEEE DEIS Web, of which Dr. Penrose is the Editor-in-Chief. The following videos are available under the Lifelong Learning button of the IEEE DEIS Website http://ewh.ieee.org/soc/deis/lifelong-learning/educational-videos.html:

- Rotating Machinery Workshop
- Streamers in Liquids: Basic Phenomenon
- Fundamentals of Motor Insulation for Repair Shops: Part 3
- Turn Insulation Aging of Motors Exposed to Fast Pulses of Inverter Drivers
- Utilizing Reduced Build Concepts in the Development of Insulation Systems for Large Motors
- Fundamental Demonstration of Electromagnetic Fields and Energy (Mass Inst of Tech – MIT)
- Analysis of Winding Failures in HVDC Converter Transformers
- Electric Breakdown in Solid and Liquid Insulating Materials
- Electrical Insulation of Gasses (A Tour of MIT Labs)

There are lots more to come!! Each runs from 20 minutes to 1.25 hours.

Anyone can become a member or associate member of IEEE DEIS. For information go to http://ewh.ieee.org/soc/deis and select the join button at the top of the page.

Also note: the videos have been improved. You can expand to full screen by right-clicking on the video and selecting ‘view’ and ‘full screen.’

Do Not Read if You are On an Airplane

2009-08-03T19:45:00.000-07:00

Several weeks ago I missed Nick’s (my older son) graduation and graduation party due to maintenance issues and airline supervisors and maintenance staff attempting to convince the pilot and aircrew to take a broken plane. I provided a copy of my editorial, published several weeks ago, to the airline the day before publishing. I received a settlement from the airline and official apology.

However, my experiences are not unique. The following article was written by a journalist for Consumer Reports: http://www.consumeraffairs.com/news04/2009/08/airline_maintenance.html

We have had a number of aircraft, both domestically and abroad, either crash or have significant problems, including many that have made the news or that individuals have experienced. The issue relates to the concept of cutting corners in maintenance, including areas that may not be considered ‘critical.’ Basically, individuals or groups who have taken the basic rules for optimizing maintenance and stretching them far beyond expectations.

Review the issue and solutions by reading the 2009 Axiom Business Book Award winning “Physical Asset Management for the Executive: Caution Do Not Read This if You are on an Airplane.” Only $14.95 USD through any online bookstore or order it locally or through our direct distributor http://www.motordoc.com/detailPAM.htm

Rotor Bar Forces Experiment

2009-07-23T20:04:00.000-07:00

A number of theories surround the forces in a rotor including those on the rotor bars and rotor core. The experiments depicted in this video determine the location of those forces.

IEEE DEIS Web Videos

2009-07-20T19:12:00.001-07:00

The Institute of Electrical and Electronic Engineers, Inc. Dielectrics and Electrical Insulation Society Website (IEEE DEIS Web) has been placed historical educational videos from the 1960s on the website under http://ewh.ieee.org/soc/deis/education/all-education-material.html. When finished, there will be more than 50 educational videos available for viewing by IEEE DEIS members. The videos each have a 2-5 minute preview for non-members. The videos available as of July 21, 2009, are:

- “Rotating Machinery Workshop:” the first video about one hour in length that describes all of the major insulation tests from their basic principles.
- “Streamers in Liquids: Basic Phenomenon:” This short video of about 20 minutes describes semi-conductive and conductive streamers within insulating oils.
- “Fundamentals of Motor Insulation for Repair Shops Part 3:” This video of about one hour and fifteen minutes discusses proper insulation systems for repaired electric motors, in particular the forces on the coils in an operating motor and the proper securing of the insulation system as described in this week’s tech tip.
- “Turn Insulation Aging of Motors Exposed to Fast Pulses of Inverter Drives:” Describes the breakdown of motor insulation systems in inverter applications. Runs about 18 minutes.
- “Utilizing Reduced Build Concepts in the Development of Insulation Systems for Large Motors:” this 18 minute video discusses the concept of using thinner insulation systems for improved thermal transfer. It requires improved insulation materials.

Additional videos will be placed a minimum of one or two per week.
For more information, contact the IEEE DEIS Web Editor-in-Chief Dr. Penrose at hpenrose@ieee.org.

Tech Tip: Coil Movement Issues

2009-07-20T19:11:00.000-07:00

During startup and operation of an electric motor, the forces on the coils of an electric motor move up and down and to the sides in the slots, are pushed and pulled in and out of the slots, flex as the coils leave the slots and move in virtually all directions in the ends of the coils. In all electric motors, the movement of the coils must be controlled while allowing for flexibility in order to avoiding fracturing the insulation system. In low voltage, mush wound machines, the paper insulation, varnish (which acts as glue), and tying tape are used to reduce the movement of the coil. In form-wound coils, the tapes, blocking, surge rings, varnish and tie tapes are used to reduce movement of the coils.

When machines are not properly secured, such as when some manufactures and repair shops skimp on insulation systems, or do not tie every slot, the movement of the conductors and coils eventually wear away the turn insulation. If additional stresses of contaminants, including abrasives and chemicals which may attack the insulation system, surges and partial discharge occur, the windings will short between conductors eventually. In other cases, if the windings age and become brittle, a poorly secured winding will generate small fractures in the insulation system in which moisture and other contaminants will penetrate and then generate pressures based upon the electrical and magnetic fields in those areas. Eventually, the insulation system will either fail between conductors or to ground. A 1983 study of motor failures indicates that over 85% of winding failures occur between conductors, and not to ground.

With electrical signature analysis (motor current signature analysis) coil movement can be detected and monitored during operation. When the machine is running, there should be no movement with coil movement signatures indicating a poorly secured winding. The signature is the speed (in hertz) times the number of slots in the stator plus and minus the line frequency.

The sign of coil movement does not necessarily indicate that the winding will fail in the near future, but that the winding is weak. In some cases, this may be an issue in the original design of the machine. However, if the signature did not exist before a machine repair, then it is an indicator of motor repair defects due to either a misunderstanding of the forces in the machine or lack of insulation material.

Impact of Lean Maintenance

2009-07-20T19:10:00.000-07:00

I have observed the impact of ‘lean maintenance’ on everything from rotating machinery to the maintenance organization and the application of lean to the business organization, overall. The original purpose was to streamline processes and eliminate waste in all areas from communication to physical movements. The problem is that the term ‘lean’ has been used not only to trim the fat of organizations and processes, but also to make deep cuts into the muscle of the organization.

The ideas fostered by such programs as lean, RCM and re-engineering were to reduce the focus on unnecessary tasks and to assist with focusing resources. For instance, if you are looking at three different systems: one critical; one redundant; and, one unimportant, these programs started as methods of using set criteria to determine the level of attention for each type of system. Occasionally it would even be determined that the best practice was to let a piece of equipment to ‘run to failure.’

How we graduated from this concept to only a few pieces of equipment would be maintained and the rest run to failure has been a sight to behold! In effect, ignorant abusers of such programs have used the tools as a means to justify degrading their maintenance organization and workplace to one of reactive maintenance. The result has simply been a disservice to their organization and the bottom line.

What we have forgotten is that if a system was unnecessary it wouldn’t be there in the first place. So, technically, if something isn’t worth any notice at all, why not remove it? Well, you say, it isn’t cost effective to perform maintenance, so it was run to failure, but we still need it. Let’s say the item in question is a bathroom fan.

Is the bathroom fan a piece of critical equipment? (OK, I have heard the jokes and comments that you have just considered… ha ha). Let’s look at it from several perspectives: 1) Does it impact the four areas considered in RCM? (Safety, production, regulation or cost); 2) What is the reaction if it fails unexpectedly? Does it get repaired eventually? Immediately? Are complaints generated? 3) Why was it installed in the first place? Basically, is there a cause-effect relationship with the fan? Could it be that there is a regulation for air turnover, or just that such ventilation exists?

Now, let’s add in the headache factor and the real reasons for reduced maintenance. Often the case is related to the wrong maintenance being performed, other times it is a lack of understanding, and, in others, a lack of political will to maintain the maintenance organization. When times get tight, one of the first budgets cut is the maintenance organization. Once times and resources return, the mountain ahead is steep and the resources and effort, even the will, is lacking to move forward. As a result, the use of the maintenance organization to ride through cash-flow and budget shortfalls compound the destruction of the maintenance organization itself.

The roughshod methods referred to as ‘lean,’ various forms of ‘modified RCM,’ and concepts in which they attempt to refer to ‘re-engineering,’ outside of the original concepts, are often used as tools by consultants to make the end user feel better about gutting their maintenance organizations while paying significant fees. While a consultant, I railed against such practices after seeing the results over and over again. But, how do you explain to a prospective client that their ‘baby is ugly?’

Now, I have an organization and facilities in which we are implementing the common sense approaches that I have been preaching for decades. Seeing as we also provide condition-based PM, predictive, corrective and engineering resources for our clients, we also extend this approach and our recommendations for their success.

Howard W Penrose, Ph.D., CMRP

http://twitter.com/motordoc

Come visit the Dreisilker organization at http://www.dreisilker.com!

For questions, please respond to this email or contact me at hpenrose@dreisilker.com.

Motor Repair ‘Half Life?’ Reality or Myth?

2009-07-13T19:28:00.001-07:00

It actually depends on the quality of the repair. A quality repair process can provide an average life of 20 to 25 years, as with a new electric motor. Motors that do not survive that long normally have some type of some issue such as contamination, operation, too many starts, electrical or mechanical anomalies, and other issues that reduce their life.

As was determined in the Canadian Electrical Association study, “Evaluation of Electric Motor Repair Procedures,” a quality motor repair process will maintain the original efficiency of the motor. In particular, rewinding using a mechanical process will maintain the losses of the stator whereas higher temperature processes, such as burnout, increase the eddy-current (stator) losses. Increased losses result in reduced efficiency (an average of an increase of 0.5 to 1% per rewind) in which the losses are seen as higher operating temperatures. The higher temperatures, or even hot spots in the stator core, reduce the insulation life at that point. To check for core damage, a before and after core loss test should be performed on all motors that are burned out, or the core is damaged, and there should be no change in the core loss with an upper limit of about 6 Watts per pound.

Additional issues include that 81% of motor repair facilities modify your windings through the repair process with 73% of those modifications for the convenience of the repair facility. Improper modifications to windings will result in changes to the efficiency of the motor and may result in increased stator I2R losses and possibly even rotor losses, depending on the result of the modification. These changes also increase operating temperature, also resulting in a reduced thermal life of the motor.

The results may be seen as slight increases in operating current under the same load conditions, hotter running motors, reduced efficiency, the motor tripping upon return from repair, reduced mean time between failures, and other anomalies, including significant changes to soft foot due to mechanical changes in high temperature ovens.

For more information on the impact of improper motor repair practices, go to http://www.motordiagnostics.com/presentations.htm. A number of papers can be found on the electrical and mechanical impacts of motor repair.

Impact of Losing the Basics

2009-07-13T19:27:00.001-07:00

I have been working my way through converting historical training videos for the IEEE Dielectrics and Electrical Insulation Society website (IEEE DEIS Web). It is amazing how much information we have lost from the time when testing and test equipment required an engineer and not some of the modern equipment that has come along over the past decades.

The first one that we converted from tape to DVD and now to online digital format was the ‘Rotating Machinery Workshop.’ This video located at http://ewh.ieee.org/soc/deis/education/video-detail/education/rotating-machinery-workshop.html and is from some point in the 1960s. The video walks through the manual tests and explanations for insulation testing that we take for granted through modern test instruments. The result is the loss of the fundamental knowledge as to what the tests are supposed to tell us versus concentrating on the pass/fail values.

One of the recent ones that we are presently working on discusses ‘Fundamentals of Motor Insulation for Repair Shops,’ of which only Part 3 has been recovered, so far. However, in this hour and fifteen minutes, the presenter discusses, with pictures, calculations and descriptions, the electrical and mechanical dynamics of an insulation system that prematurely age the system and cause it to fail. This includes the forces on the windings through to the impact of contamination, vibration, coil movement, and other forces (vectors) that will take an insulation system from an average 20-25 year life down to a matter of a few years. It even shows the calculations in order to determine the effective age of the insulation system due to its operating environment.

In both of these, and other videos, if you are a member of DEIS, you have full access 24/7. You do not have to be an engineer and can get more information from clicking on the ‘join’ button at the top of the page at http://ewh.ieee.org/soc/deis

I suppose it is amazing how quickly we are able to lose key information that would help us interpret the problems that we run into with modern technologies. I even remember having a ‘discussion’ with an individual who was determined that windings only moved up and down in a slot because in a textbook it was dealt with as a static system. However, as identified in ‘Fundamentals of Motor Insulation for Repair Shops,’ they identify all of the different directions and forces involved during the operation of the machine. Even I had not fully grasped all of the forces and found the video to be very educational.

Over the past years I have met newly graduated engineers, from reputable schools, that do not even know how insulation resistance testers (ie: Meggers) work, tradespeople that do not understand how to use voltmeters and ammeters to troubleshoot motors, do not understand the differences between RMS, True RMS, and Averaging meters, and worse. We have drifted so far off the basics that engineers and tradespeople have difficulty explaining to lay people that an insulation to ground test cannot detect winding shorts!

While I am a strong believer in modern technology, future technologies, and have a fondness for computers, I have always found that it is important that I understand the basic principles behind what I am doing. Sure, you may want to start out just understanding how to perform the test. But a true professional is going to dig so that they understand the limits of those tests and what they really tell us.

For information on the basics:

http://www.motordiagnostics.com/presentations.htm
‘Electrical Motor Diagnostics: 2nd Edition’ at http://www.motordoc.com/detailEMD.htm available through our distributor or any online bookstore! (yeah, well I use the sales to support this newsletter).
IEEE DEIS Videos: http://www.ieee.org/go/deis and under the ‘Lifelong Learning’ button at the top of the page.

Want to know more? Watch for our MotorDoc Tech Tips in these newsletters!

Sincerely,
Howard W Penrose, Ph.D., CMRP
howard@motordoc.com