Motor driver test equipment

What sort of motor drive and what sort of tests ?

The range of power ratings and possible tests is so huge that you need to narrow things down a bit.

Testing even modest ( a few kW) motor drives at full power is difficult and quite expensive.

MK

Hi! And thank you for your time!

i was asked to repair diffrerent stepper motor drivers. From 100W to more powerfull drivers. I need a testing mode after the repair is done. I cannot give the client the motor driver and recive a negative feedback. I need something to test the functioning of logical part and something to test the power part. But i cannot find any information about this. It's the first time that i'am trying to do this and i'm a little stuck in here.

You can do a lot with basic test equipment like DMM, Oscilloscope and logic analyser. (You may need an isolated 'scope for higher power drives.) A current probe (for the scope)  is useful but quite pricey. To test the complete drive at this sort of power level you can't beet using an actual motor as the load. You'll need some kind of mechanical jig to hold it and to apply mechanical loads. Fancy drives may include some kind of positional feedback and once again there is no good substitute (unless you are testing a LOT of drives) for just using the real parts so your mechanical jig will need a way of mounting the position sensor for the drive.

It's expensive to set up for each different configuration so unless the numbers are large you may do better to test the drive in the actual operating set up.

Why is the client asking you to fix these drives - is there a reason they can't go to the original supplier/manufacturer. I ask this because you will need to make an investment in testing and learning how to fix the drives and you need to be sure you aren't just competing on who'll do it for the least money.

MK

The ideea is to fix this drivers with lower cost than the producer. Money will be alocated for test equipment but this is the problem. Where to buy? Do you have documentation about fixing this kind of drivers? Generaly speaking.  Is there any software to send information to driver? Can you give an example of testing with oscilloscope or with logic analyser. I want to learn but no information found. Hope i'm not boreing you. I'm new in this and anxious to learn. I have the basics, but no info about this! My knowledge in stepper drivers are small but ready to learn.

I don't want to be a pain here but it sounds like a total non-starter. If you having to ask such basic questions how can you possibly expect to compete with the people who designed the stuff in the first place ?

For example, "Is there any software to send information to driver?" -  all drivers are different and need different software to test them. The manufacturer will have written this as part of his design process but probably won't want to share it with you so the chances are that you would need to write it yourself.

If you are determined to give it a go then get all the manufacturers data and service information for  a typical drive (that you might want to fix) and try and work it out from that.

As far as standard test gear goes then that's easy to buy. Special stuff like mechanical test rigs you'll need to design and make yourself (or pay huge amounts to get some one else to.)

MK

Ok! In the way that you put the problem no body can learn anything or everybody who is doing well on a domain was born with the knowledge. I thought that in here i will find people that will share information or try to help anyone even beginers. It seems that i was wrong. Sorry for making you loose time. here's how i see things. From my experience the moast common problem with industrial motor drivers is the power supply part that usualy is getting broken because of the heat that is generated. I had a number of drivers fixed but all tested on the application. Now i want to fix them and to be able to test them in the workshop. If you have information share, if not just say you dont have or you dont have knowledge about this kind of equipment. Dont say, hey you are a starter and you dont know what you are doing. Nobody borned with knowledge. Everyone started to learn on somepoint and learning takes until die. Anyway sorry again for loosing your timed. It seems that is a common problem on all forums.

I'm not very impressed by your approach. You're cross because I've told you that your business plan is unlikely succeed but I also gave you some advice which you seem to be determined to ignore.

So let's try it again - get the manufacturers data and support material for a drive you want to fix - and then if you can't work out how to test the thing you'll be able to ask the kind of question that can be answered.

I've already told you that you can get a long way using basic electronic test equipment.

Forums like this are good for getting answers to specific questions but for basic learning you'll need to go to college, work for someone who'll train you or self teach via the internet.

I'll help you once more - then it's down to you and you'll need to work at it (I don't mind helping beginners but I can't help people who can't be bothered to work.)

I Googled "stepper motor drive testing " and got this hit on the first page:

Stepper Motor Driver Test Fixture Design

Read it - if you don't understand something then come back and ask.

MK

Hi Michael,

I find your reply to this situation very clear and patient. Most of the time beginners do not have a way to appreciate the complexity of the questions they are asking. I agree with you that the best way to test is to set up a situation where the boards can be tested on a application piece of equipment. When I did this years ago the manufacturer supplied a couple old pieces of machinery that we could install the boards into after repair and test them. If Stanulet is working on a variety of boards of course this may not be practical. Learning is a step by step process.

John

Great example! If i understand well that guy is commanding the motor driver by arduino. But this still includes a motor and an encoder. Somebody told me that i can use a dummy load on the output of the driver but i have to find a way to calculate it. I think i can find a sotware and an interafe board from TI. But still remains the problem of load.

Hope you dont mind that i put a comment on your post. Yeh learning is a step by step process. But if you get help or guidance learning is more easy. At my workplace i have 14 men under my care. I try to teach them everything i know in what we are doing there. I never discourage any of them. |And the most important thing i never tell them "Ohhh you are a beginer and can handle this or that" I give them courage and guide them to manage by themselfs. And as a matter of fact i do apreciate the complexity of the question. Thats vhy i was guided to this forum. I was told that here are great people ready to help.  I didnt know that here is no place for beginers in one domain or another. Still i hope that this was a misunderstanding and the thinks will evolve in a good direction.

I never liked to arguie with people but i do not like to be treated like a person that is not capable to learn. I am a beginer but i'm realy capable to learn. So once again thanks for your time and advices!

Hi Stanulet,  Welcome to E-14. You have just inspired a nice lively discussion. I agree with you that a misunderstanding is at the heart of it. We are often asked questions without knowing anything about the experience or age of the asker. The asker often assumes that we know everything about their situation and their problem.  I can Assure you that the first person who addressed your question michaelkellett is among the most comprehensive and competent engineers anywhere. There may not be a simple answer to your question if he didn't give you what you were looking for. Once again welcome to E-14. I hope you stick around and lend some of your knowledge and experience to help other people.

John

Hi did you ever solve the problem of testing your drives? I have worked on a number of motor drive designs and test systems, everything from simple cheap bench top tests to multi-million pound test cells. Please give a bit more detail if you want to set up a loading rig...Peter

Hi did you ever solve the problem of testing your drives? I have worked on a number of motor drive designs and test systems, everything from simple cheap bench top tests to multi-million pound test cells. Please give a bit more detail if you want to set up a loading rig...Peter