Something need to be considered in buying AC drives

Here are my top picks, in order of importance:

Application: the AC drive must be appropriate for the task at hand, as the others before me have said.

Appropriateness: but also, the task at hand must be appropriate for using a drive! Too often lately I have seen people try to apply an AC drive to a machine that had no business having an AC drive applied to it. There was zero value in varying the speed. Just because you can, does not mean you should.

Support: whatever AC drive you pick should be from a supplier who is as LOCAL as possible and can support you when things are not going as planned. Most use the same or similar technology (otherwise they would not survive in the market) and every drive works great when you commission them, until it doesn't. That's when the value of a good local supplier arises. Toll free numbers are great, but if your down time is costing you a lot of money per hour, what difference is the price of a phone call going to make anyway? What you will want is that someone will BE THERE as fast as possible to get you back up and running.