[Al321]

TS Series 3 Axis 12.0Nm(1699.68oz.in) Nema 34 Closed Loop Stepper Kit w/ Power Supply

[joeavaerage]

Hi,
that is NOT a servo....it is a closed loop stepper and the manufacturer would have you believe its as good as a servo...its not.

All steppers lose torque the faster they go....thats plain physics and a closed loop stepper suffers the same thing.
If your stepper misses a step, it must be slightly overloaded at that speed, otherwise it would not have missed a step right? The drive
will insert an extra step to catch up, but guess what the extra step is just as likely to be missed as a regular step.

Closed loop steppers can and will fault out if too many steps are lost rather than continue and wreck the part. They can also accurately interpolate
between steps and therefore offer greater resolution than an open loop stepper. These are advantages but you pay a premium for them.

What a closed loop stepper does not do is:
1) Go faster
2) Have more power
3) Have higher overload capacity.

These 12Nm steppers are a poor choice, many get sucked into buying them because of all that torque...right? But they run out of steam at about 500rpm.
There are much better steppers with only 3-5Nm but will still have useful torque at 1000 rpm plus.

Steppers have no overload capacity, when they get to their maximum at whatever speed, any extra load and they stall, no ifs or buts, they just stall. A servo, either a
brushed DC servo, a brushless DC servo or an AC servo will have three to four times its rated torque as a temporary overload. When a servo gets overloaded it jut 'digs in' and
delivers more power.

In short a well chosen LOW INDUCTANCE open loop stepper and the HIGHEST VOLTAGE DRIVE/SUPPLY will match any closed loop stepper.
If you really want closed loop performance then get genuine AC servos like Delta B2 series or DMM.

Craig