AC DRIVE

Is your question related to AC motor?

If so, It run torque mode when start, and vari speed when running.

Posting in CAPITAL LETTERS in a Forum Post, is regarded as bad manners - it is like shouting loudly at the reader.

Because your question is formed badly, it is not possible to assist you correctly at this time.

Please re-form your question (Not all Capital Letters, thanks)....

Most applications use in Constant Torque mode.If u can be more specific interms of application, speed variation etc probably a better answer can be foud.

ACS8OO?????, DRFIVE IN TORQUE MODE THE SPPED OR IN OUT THE SPPEED AGAIN.

GOTTCHA?

Wangito.

I'll take a stab at interpreting (or misinterpreting) the OPs broken English.

The ACS800 drive, like many other high-end AC drives, is capable of operating in Torque Control mode or Speed Control mode. I think maybe you are asking when you would use one or the other.

99.9% of applications of Variable Speed Drives are going to be Speed Control. That's why you use a Variable SPEED drive! But there are the occasional exceptions where Torque Control is beneficial.

Basically, the only time one would use Torque Control mode would be in an application where maintaining precise control of the torque of the motor takes precedence over the speed. A classic example that may help illustrate it is a wire coil winder. You have pay-out reel and a take-up reel, usually the control is on the take-up reel. As the reel fills with wire, the diameter changes and thus the speed at which it is pulling from the pay-out reel is changing. To keep the pay-out reel from spinning too fast out of control then, you have a brake, a "dancer" weight or another motor maintaining a mechanical resistance to the take-up reel. But more importantly, if you pull too hard with the take-up reel it will stretch the wire and make it thinner. So even though you are changing the speed, maintaining the proper torque, i.e. the pulling force, is the more important thing to consider. In that case, you would put the drive into torque-control mode so that it will maintain a programmed maximum torque and sacrifice speed in order to do that.

Another example is when you have 2 motors driving the dame load, connected to a common shaft. An example is on large variable speed rock crushers, they often use 2 motors on opposing sides to maintain balance on the bearings. Both motors are belted to the same drive shaft, but if one motor has more slip than the other, it will try to drive the entire load, not just 1/2 of it. So you put 2 drives on. Drive #1 is in Speed Control mode, drive #2 is in Torque Control mode. The commanded speed reference goes to the Speed Control drive, it then sends out a torque output signal to the second drive, which then uses that as a commanded torque response. That way, motor/drive 2 is always outputting the same torque as motor/drive 1.

-JRaef,

Good intelligent answer. It was a pleasure to read it because I learned something.

I always feel a little sorry for the people from non-english speaking countries trying to communicate their thoughts. I think you did an excellent job of interpreting what was asked followed by a very good answer.

You can raise the good answers to 6 now... although, I have a feeling all your answers are good.

Thanks again,

Randy

Jraef at his usual best..and Randy...excellent obeservation and mature attitude in underlining that not all speak/write good english and their intention is only to gain knowledge from this excellent forum.

"Focus on Technicalities,... and not on personalities" was a quote i saw on another forum.

Keep up the good work guys..

good answer.

Excellence answer!