TMCM-170

[Paul Frattaroli]

I have a technical question regarding the TMCM-170 modules we ordered not too long ago.



We are using the TMCM-170 module to drive a “maxon EC-max 30” brushless DC motor. The motor’s maximum current is rated at 1.5A @ 24V. We have set the current limit to 1A in the TMCM-170 IDE. We also verified the readings and settings as mentioned in section 3.2.1.1 of the “TMCM-170 Reference and Programming Manual”. However, what we have noticed is a discrepancy between the current reading of the TRINAMIC module and of the power supply we are using. The TRINAMIC module reports 1A whereas our bench power supply reports about 0.3A current draw. The TRINAMIC module is set to block commutation mode (2 motor coils switched on at a time). Our problem is that our motor cannot generate the expected amount of torque and we suspect that it is not getting sufficient current.



Do you have any information regarding this?

[TRINAMIC_BD]

The motor torque is proportional to the motor current. The motor power is seen at the power supply. It is P=U*I, or P=torque*veloctity [RAD/s]. This means, the power supply reading does not correspond to the coil current, but to the power consumption. You should increase motor current limit.