Re: lost steps

Jerry,

Can't believe no ones mentioned this before. (even I missed it in my
long post)

What CURRENT are the drivers set to!?
What VOLTAGE are the motors rated for?
What CONNECTION (series or parallel) are you using in the motors?

You may be saturating the windings of your motors. This would act a
lot like an interference problem, and since you have mentioned the
BARE motor shaft rotation, I should have caught this earlier. The
effect(s) of oversatuturation is more noticeable on lightly loaded
motors.

Steppers are a spring-damped system, and work best with a load on the
shaft,it damps the "ringing" at the end of each step. This is also
why half-stepping often works better; the distance moved is shorter,
so there is less "ring".

When motors are over-driven (usually in the interest of "more
torque,please") their behavior becomes erratic. They can get too hot
and if run this way too long, become LESS powerful as the magnets are
destroyed in the process!

Try reducing the current output to the motors! Next try using a lower
voltage supply. I know you are using 37V from your reply to my post;
this SHOULD be ok (for most motors), but when you're in the middle of
an alligator filled swamp, you do things you wouldn't NORMALLY do.

Mariss in an earlier post told what factor the voltage can be
increased to (above the nameplate rating) Are you beyond this at 37V?

Sorry I missed this before. Good luck!

Ballendo