I knew form the beginning that the knob to dial in the speed did not react accurately. But now it is even worse. I can turn it very fast, and nothing happens, when I turn it slower, it moves sometimes, sometimes not. I was trying just for the sake of testing to dial in 20.000RPM...so that was impossible, it jumped from 19800 to 20200 or more. I know it makes no difference, but it is frustrating that when I want to slow it really down fast, it just seems not to be responding.
I am a new owner of an AR8 and have the same issue. Came here tonight to see if anyone has the same problem. Sounds like others have seen this too. Please post what you find out so we don't have to individually contact support.
Pasting Chads answer here. I think it is the way it is, we just need to get used to it. Will try out his suggestions.
The Seimens VFD can be tricky.
When adjusting the RPM….turning the dial slowly, should show an small adjustment of about 6RPM per click. But turning it faster does not really impact this.
Turning it consistently is the key.
If you need to move from 24,000 to 18,000 for instance, turn the dial consistently with no big pauses and the steps it makes will adjust automatically from those small 6RPM steps to larger steps up to 1000RPM in size.
But it can be difficult to fine tune quickly, as you can so easily over shoot the intended setting.
I believe the guys cover that VFD and the others in a bit more detail here:
Pedro thanks for posting your update. I went to watch the video and it does appear that mine is working much like that. I'm sure that I will get the feel for how quickly to rotate it to make better adjustments.