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How to monitor the current of the motor (stepper motor)? Answered

or is there any current sensing device or module available in the market?

I want to monitor the the current [ from +ve terminal of the power supply to motor ] and the current [from motor to -ve terminal of the power supply] 

please suggest me any method to follow or is there any circuit module or device is in the market. so that I can buy and use them into my project to achieve this goal. 




2 years ago

I have a Fluke DC clamp-on Ammeter.

BTW the current measure on the high line will be identical to the low line current.


1. Current can be derived from the resistance of the coils and the voltage across them

2. You could measure the resistance of the leads and calculate the current from the voltage across them.

3. you could insert a very low value resistor in the power leads and measure the voltage across the resistor to derive the current through, the current through the resistor is the same as the current through the coils.

1.) You can't ignore the inductance of the coils, since they're switched....

Is there any suitable sensor module (circuit board whuch used to sense the current), can anyone suggest me which sensor module is good to sense the current of the stepper motor?


AC amp meter it uses the EM field off the conductors to sense the current.

Yea. I am thinking, I can find some current sensor from the market. Can anyone suggest me which current sensor is suitable for stepper motor if anyone experienced with it ? So that I will be sure to go for the right product.


What drive chip are you using ? Many of them have a current sensing pin which you can access

Not really easy for a stepper motor as they are driven by a PWM signal.
Usually it is easier to check the current based on the controller settings or by measuring the current draw of the controller and neglecting the losses of the controller itself.