11/4/2016 1 Comment How smart can a dumb motor get?![]() I have a friend in the industry who gets upset when someone tells him “My AC motor quit running right”. His response is always something like, “It’s not the motor. The motor is dumb. If you apply the proper power and if there’s no issues on the load side, it’s gonna do what it’s supposed to do or not run at all”. Which is essentially true. Sorry motors, but your just not all that smart. Except maybe DC and servo motors. Even with those though, the brains are mostly in the drive controls. Could an AC motor be made smart? You could argue that by applying a VF drive it’s now smart. It will speed up and slow down on demand. But those are normally mounted several feet away or even in the next room so not an integral part of the motor. Not that it couldn’t be mounted in an oversized junction box but why do that? Drives are typically electronic devices and prefer a nice comfy control room environment away from the heat, vibration and contamination that those dumb old workhorse motors live in. It could be done though. Who knows, maybe someone is already doing it. Okay, so our motor can speed up and slow down by itself, now let’s imagine it’s smarter yet. It senses incoming current and controls start up torque very slowly to avoid stressing its copper muscles and insulation ligaments. No mechanical stresses from the winding flexing in this smart guy. And once up to full output, current and voltage are sensed and kept in near perfect balance through an integral variac or some other new technology. This is all already doable and being done in a few cases but external to the motor with surge suppressors, chokes, variacs, soft starts, etc. Now let’s look at the smart mechanical features. Ultrasonic sensors could tell the motors brain its bearings are needing a fresh squeeze of lube and it’s automatically added. In fact, let’s get smarter yet and measure the bearings operating temperature and have it add an appropriate rated compatible grease for the current operating conditions. The ultrasonic sensors would also detect when just the right amount of grease has been added. Of course, our smart motor also protects itself from outside contamination with mechanical seals on both ends. Stray shaft currents are mitigated with insulated ceramic coated bearing housings and integral grounding devices. And the cooling system is thermostatically controlled with high speed fans and high surface area fins to quickly dissipate the heat and keep the temperature just right regardless of the motors operating speed. This will also improve efficiency by eliminating the drag caused by the cooling fans rotation when it’s not needed to run continuously. Yeah that’s all well and good you say but what if the motor wasn’t installed properly and there a misalignment issue? That’s where the integral “SmartBase” comes into the picture. With pressure sensors on the bearings the motor automatically adjusts itself with a series of tiny electric jack screws to maintain perfect alignment and load balance on the shaft. But let’s not forget external communication and the industrial internet of things. If the smart motor needs a human to intervene when it’s systems fail or aren’t enough to self-correct it calls or texts you and asks for your help. Not just a generic call for help but something like, “I’m sensing pressure on the right side of my drive end bearing and can’t seem to correct it. I’ve run my diagnostics and it seems the drive side horizontal jack screw is non-responsive”. Or maybe the request for human intervention is just for a simple task like replacing a lube cylinder. Then the call might go something like, “I’ve just dispensed the last of my high temperature grease. Please replace in the next 10 days before my next lube cycle”. Maybe despite all of the smart features in this motor it still needs an occasional recondition. It could alert you to this fact and send notifications to production and the plant manager predicting when the bearings will fail and start damaging the motor if not shut down and removed. It could even notify the repair shop what parts will be needed and when the motor will be available to be sent in. Although some of this is probably impractical, as the cost of sensors comes down and new products are brought to market who knows how smart our dumb friend will become.
1 Comment
Condition based monitoring of your plants assets can get pricey. American MTS has many of the devices needed for this currently in our toolbox including vibration analyzers, a laser alignment kit, ultra-sonic test equipment, infrared cameras and a variety of electrical test equipment. We have invested more than $250,000 in these tools so our customers won’t have to. This large upfront investment in equipment and training to learn how to use and understand the data collected from them makes setting up a condition based monitoring program cost prohibitive for smaller companies. Are there other options with a lower price point and learning curve for the do-it- yourselfers? We were asking ourselves the same question. This led us to research different options currently available. After looking at several lower cost options we decided to become distributors for the one that we believe gives the best bang for the buck. ITT has developed a device called the i-ALERT2 that is smaller than the palm of your hand, will continuously monitor vibration and temperature while costing much less than traditional options. In fact, for less than $500 you can monitor your asset from your smart phone or tablet. Let’s take a closer look at this powerful little tool. As you can see from the above picture the i-ALERT2 has a very small profile that makes it easily installed in tight places or on smaller applications. In addition to its small profile, the device is also water resistant, has a battery life of 3-5 years depending on usage and communicates to your smartphone or tablet with a free app. Like Yoda from Star Wars, you can’t judge the i-ALERT2 by its size. The i-ALERT2 can be installed in several configurations including epoxy, magnet, or hard mount with a tapped hole. Vibration is measured in three planes: horizontal, vertical and axial. Whenever possible, the light should be in-line with the shaft to ensure these coincide with the app. Once you have decided which method of installation is right for you and it is set in place; simply remove the sticker from the device and it will begin working its monitoring magic. Once the sticker is removed it powers up and begins taking readings. The device will track vibration and after 25 hours of run time will automatically set its own alarm parameters 25% above average recorded values. You can also alter these parameters within the app if you are experiencing frequent unwarranted alarms or want even tighter monitoring bands. After confirmation of change the app will communicate with the i-ALERT2 to set the new limits. You’re now locked and loaded. The lights on the i-ALERT2 provide a quick reference guide. The device will flash three different colors LEDs. While everything is running well and inside acceptable parameters it will flash green. If a measurement is above the alarm set points the light will flash red and the time and date of this occurrence is recorded. While the app is communicating with the i-ALERT2 the light will flash blue. Now that everything is set and running, what’s next? Well, that’s really up to you. You can use the device by watching the lights to know when there is an issue. You can create a periodic route to download the information from your i-ALERT2 for trending data over time. If alarm conditions are occurring, you can compare the FFT graphs to readily available sample charts or send the data to American MTS and we will analyze and report back our findings to help you determine what steps are needed to correct the issue. The device automatically checks for alarms every five minutes and records FFT vibration and temperature data once per hour. As you can see this simple device can make a world of difference in allowing you to keep a close eye on your assets health. If used properly the i-ALERT2 can help you catch a failure long before it becomes catastrophic greatly reducing the repair cost and eliminating unplanned downtime. At American MTS we are constantly striving to help our customers reduce stress and rest easier. We believe that this powerful device is worth considering to help you feel more at ease when you kick off your boots at the end of the day.
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ArchivesCategoriesAuthorMichael Huber is President of American MTS an EASA accredited service company located in the Carolina's. |
Monroe Service Center |
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