For EVALPOWERSTEP01 we are looking for the current relation between parameter set current like Acc. Current, Dec. Current, Hold Current, Run Current and the actual current consumption of motor.

[Suryakant Mane]

We are evaluating the powerSTEP01 with the help of evaluation board. We have configured the current parameters like Acc. Current, Dec. Current, Hold Current and run current for different set of current values step by step (Please refer the attached excel report). Motor consuming the current less than this configured current value. We want to know the relation between the set current and the actual current consumption of motor. Please refer the attached report for 3 different motors.

Thank you!

[Suryakant Mane]

@Cristiana SCARAMEL​ Please help us in above query as soon as possible.

Thank you!

[Cristiana SCARAMEL · Accepted solution]

Hello @Suryakant Mane​

Motor consuming the current less than this configured current value. 

If I understand you correctly, you mean the current consumption from VS is different from the value you expect, is that correct?

We want to know the relation between the set current and the actual current consumption of motor. 

An estimate of current consumption considering a set current of Ipeak on both full bridge (working in full-step) will be approximately: 2 x Ipeak x D (where D is the duty cycle).

The D can be calculated as the mean voltage to be applied to the engine to have Ipeak (Rmotor x Ipeak) divided by VS (supply voltage).

Let me know if these info are useful to you.

[Suryakant Mane]

Hi @Cristiana SCARAMEL​ Thank you for your valuable response. Your answer is very much informative and helpful to us.

We have some queries further.

Stepper motor used

Fulling - FL57STH56-3006A

Motor resistance - 0.75 Ohm

Inductance - 1mH

PowerSTEP01 Driver settings

Operating Mode- Current Mode

Current setting - 0.94 A

(Run ,Hold, Acceleration & Deceleration Current)

Micro stepping - 1/8

FS_SPD - 2333 steps/sec (700 RPM)

(Automatic switching to full-step)

All other setting - default

Stepper motor tested for 0 to 2000 RPM

Question 1 : Are the current setting values (Run, Hold, Acceleration & Deceleration Current) in RMS or peak?

Question 2 :In another scenario, to increase the torque we are keeping configuration same as mentioned in above case, except by increasing the parameter current (i.e. Run , Hold , Acceleration and Deceleration Current) values to 2A and 3A, in this case the motor is stalling above 500RPM and 400RPM respectively. What might be the possible reason for stalling?

Question 3 : We further trying to relate this parameter current (i.e. Run , Hold , Acceleration and Deceleration Current)

to motor current and further to the torque. How should we do the calculations?

As you have mentioned in above reply,

"An estimate of current consumption considering a set current of Ipeak on both full bridge

(working in full-step) will be approximately: 2 x Ipeak x D (where D is the duty cycle).

The D can be calculated as the mean voltage to be applied to the engine to have Ipeak

(Rmotor x Ipeak) divided by VS (supply voltage)."

In our case Ipeak is 0.94A, motor resistance is 0.75 Ohm and supply voltage is 24V,

Question 4 : Could you please let us know with above settings what will be the estimate of current consumption ?

Will you please elaborate this statement in more detail.

(i.e. Ipeak = Parameter current?, The term "mean voltage"? and the formula to calculate D.)

Please let me know if any information you required further.

Thank you!