Lenze SMV Training Lesson 11: Diagnostic Fault Monitoring, History And Troubleshooting – VFDs

About This Video

This video will cover diagnostic fault monitoring, checking fault history and troubleshooting the Lenze AC Tech SMVector Variable Frequency Drive (VFD). Although most issues that occur with the SMV are setup issues, there can be faults that may occur during normal operation of the drive. This video navigates you through using the manual and parameters to decide the best possible approach to resolving your fault or issue. It also covers some basic troubleshooting techniques and common faults our customers encounter.

Video Transcript

Hello everyone, this is Craig Chamberlin with Precision Electric at precision-elec.com. We are your industrial drives, motors, controls specialists; pretty much anything involved in the business to business industrial world we have done, been doing it for a long time.

This video is going to cover fault diagnostic error messages in the SMvector variable frequency drive. Now these drives dont fault often unless there’s something truly wrong with your setup or with the drive itself. So thats basically what this video is going to cover is some of the fault message inside the manual. Speaking of which, if you dont have the manual with you, you should probably have it with you if you are gonna watch any of these videos because we are going to go over the section 5 Troubleshooting and Diagnostics section and we are actually not going to cover all of them. What I am going to cover are the most frequently occuring; we get phone calls, you know, every couple time, every, well, probably couple times every week with somebody dealing with something thats related to the SMvector drive, not because its a bad product, just because we sell hundreds of them. So naturally we run into the few anomalies that do occur and they only really fall into a smaller, specific category of faults. But if you dont know your fault code or its not covered in this video, all the fault message are right in the back of the manual and it does have, whats kind of nice is it has this status and warning, in other words the fault message, and it tells you kind of a description of what it means and then it give you possible fixes or remedies.

So the first one I want to cover actually is the Fast Current Limit. So its an FCL will flash on your screen. Fast Current Limit basically says that you are currently exceeding or your motor is currently exceeding the amount of work or amount of load that youve rated it for, but it isnt tripped yet, so FCL is basically a warning. So if it does stay in FCL for too long, youre going to risk getting a current or motor overload fault, which is actually a, lets find that fault here that way I dont mix it up for ya. That one is the FPF fault, so if you ever get an FPF fault, that is a motor overload fault. That basically means you have excessive load on your motor. Now theres two ways to fix an overload fault, first of all you need to make sure your motor isnt overloaded. So in other words, it didnt lock up or your load got locked up. You also need to make sure your motor isnt shorted, but uh, the other option is to actually go in and make sure your overload is set properly and thats parameter 1, I dont want to say the wrong one, I believe its 110, could be 108, dont have them all memorized just yet, yeah parameter 108. So you want to make sure parameter 108 is set correctly. And again, that suggestion is actually in the motor overload recommend uh, in the remedy section of the motor overload fault.

Now the second most common fault I get, or I get people coming out with is the FHF, which is a High DC Bus fault. A High DC Bus is essentially, when your motor is running, it is a generator in the opposite direction. So, well I should say it this way, when your motor is running it can become a generator in the opposite direction if you stop too quickly. So if youre running say 1700 rpm and you suddenly want to go down to 0 speed, when it goes from 1700 rpm down to 0 speed, all of that energy that is accumulated from the rotation of the motor and load has to go somewhere, so it gets pushed back up through the drive and it goes into the output of the drive and then it converts it into DC Bus voltage. And that DC Bus voltage, if it gets above a certain amount, depending on your drives voltage rating, will throw a DC Bus voltage fault. So the High DC Bus voltage fault means either youre decelerating too quickly, maybe youre accelerating too quickly. First possible solution is just to extend out your acceleration or deceleration times to make sure that thats actually the root of the problem. The other problem, the other potential could be even though youre stopping within your range you want to stop, you actually need to install a separate accessory called a dynamic braking kit. Now they do make dynamic braking kits specifically designed for the SMvector drive, it doesnt have a built in brake chopper, but this kit is essentially designed to detect when that voltage comes back up through that line and it turns on and it actually pushes the DC Bus voltage out onto a resistor bank, which is part of the accessory. So that High DC Bus fault is either you have: youre stopping too quickly or you need a dynamic braking accessory, thats the number one cause of that one.

The other most common fault we occur may be just a standard, um motor output fault, or transistor fault. which is an FOF fault. This usually occurs, again, in conjunction with a motor overload, so the first fault we talked about, which was the FPF. Um, so whatll happen is its either an overload issue or it could be that your motor is shorted on the output, so you might need to get your motor tested or the third possibility is your drive output has started to fail, so you can actually get whats called an output transistor fault. So obviously the number one solution to that would be to disconnect your motor and try running your drive again. If it still gets the fault without a motor connected, then its probably in the drive. If that doesnt fault it out then you wanna reconnect your motor, you can try running it again. If it happens again, then you probably want to get your motor tested to make sure that your motor isnt shorted.

So those are the three most common faults that youre gonna get when youre actually dealing with the SMvector variable frequency drive. Theres a lot of other ones on here, such as the EPM programming module fault, which is this little program module, which can have issues, if youre say transitioning from a newer model to an even older model. Theres uh, just a standard error message, thats pretty common, just flashes ERR on the screen. And thats if you are trying to issue a that youve locked out. So, for example, if I set my start/stop control from my keypad to my push buttons and I cant start/stop from my keypad anymore, if I try to start and stop it will flash error, cause I turned off the ability. So Im trying to issue a command thats not allowed cause Ive shut it off for some reason. So if you get the ERR, thats just a programming error. Another real common one youll get is the, theres one other one on here, a High Temperature fault and thatll only occur if your environment isnt conducive to whatever the operating temperatures are of the drive. And weve had this happen every once in a while where someone will actually stick a drive inside of panel and itll accumulate heat over time and once it gets above a certain temperature, itll actually trip on this FHF fault.

So for all the other faults and possible remedies, again check out the section 5 in the manual. Theres, theres loads of feedback you can get here, check out the previous video that I went over, that actually talked about troubleshooting and looking at your outputs. Thats another great way to diagnose possible problems you may be experiencing. Or the third option is you give us a call, because our price, if you bought it off us, our price includes support, so we have a lot of real world application experience, weve been doing system integration and retrofits locally in a 300 mile radius for about 30 years. So theres very few problems you may run into we havent, at least experienced, or ran into historically. We will be more than happy to go over those with you and help you resolve them.

Again thank you for stopping by, my name is Craig Chamberlin with Precision Electric, at precision-elec.com, your industrial drive, motor, and automation service center. If you have any other questions, dont hesitate to call and well see you then.

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