Need Help!- G251 floating inputs?

[greywolf]

Hi.

I have a pretty simple question, but since I am not an electrical genius, finding the answer isn't so simple.

I am using a G251 to drive a delicate mechanism that must only be driven in one direction. Driving the stepper in the reverse direction would be catastrophic.

As it is now I have the direction terminal (terminal 9) tied to signal ground. This gives the proper direction. However I am worried that should this connection ever fail (perhaps via vibration), then the motor would reverse and my mechanism would be destroyed.

So I have thought to leave the direction terminal floating and reverse the motor phases instead. But can I do this? Must the direction terminal be tied to either logic 1 or logic 0 to be valid? That is, if I were to leave it just floating, could the drive intermittently change direction?

I've read all the gecko faqs and re-read my G251 manual but can't seem to find an answer.

I purchased some G251s upon their introduction and they have performed for me very well. I cannot believe that such a tiny drive can channel so much power; they are miraculous.

greywolf

[Mariss Freimanis]

None of our drives have 'floating inputs' because floating inputs are bad practice. Leaving Direction unconnected is the same as applying a logical '1' to the input.

Mariss

[greywolf]

Thank you for that. I suspected the input would be stable one way or the other , but for all the work I've put into my creation, I just wanted to be sure. I will try leaving the direction input disconnected and reverse the motor phases. Thank you again.