I need to know if something will burn up beforehand I plug all the circuits:
- Ramps 1.6+
- Arduino Mega 2560
- PSU 12 V, 15 A
- 2 TMC2130 V3.0 Stepper motor driver
- 2 Stepper motors 17hs3401
The driver has a potentiometer to change the voltage that is giving to the motors. Range of Vref values:
- Default: 1 V (±0.2)
- MAX: 2.4 V
- MIN: 0 V
As one person answered me in another question, I would need 3.2 V to make the motor work well (2. Ω * 1.3 A = 3.2 V). As the driver just can offer 2 A I assume that the speed will be lower and the driver will be warmer because the motor will drain more current.
Marlin Current Configuration
There is a file in the Marlin firmware (
Configuration_adv.h) where I can set the current that the driver is going to give to the motors. I do this to calculate the current in the motor XCURRENT = 1300 mA x sqrt(2) = 1838.5 mA and set the value in the file
#if AXIS_IS_TMC(X) #define X_CURRENT 1838.5 // (mA) RMS current. Multiply by 1.414 for peak current. Default 800 #define X_CURRENT_HOME X_CURRENT // (mA) RMS current for sensorless homing #define X_MICROSTEPS 16 // 0..256 #define X_RSENSE 0.11 #define X_CHAIN_POS -1 // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ... #endif
What I am going to do is to set the drivers potentiometer to the maximum and check what happens. And I will also set the current in the Marlin to 1838.5mA
As the drivers have less voltage to give to the motors, are my drivers going to burn because they will have to give more current for a long period of time? Or will the stepper motors burn because they won't get enough current or voltage?
I also found some other possible problems in this other answer
If the current is too high, you lose the linearity of micro-stepping. If the highest current exceeds the maximum, then the highest current micro-stepping positions will collapse on each other.
If you are within the specs of the motors, there are no motor-related problems caused by higher currents.
But other problems can be caused by increasing the current. The current must be within the capacity of the motor drivers and their heat sink. If the drivers overheat, many will simply shut off, causing the motors to not move when they should, which will appear as misalignment on X, Y, or Y.
This other person also told me
you set the power level for the TCM2130 to more than 50 % then it will overheat. However, it may only do so when running at low speed. I doubt it will overheat if running at a high speed
The TMC2130 drivers can tolerate a motor operating current 1.2 A (peak 2 A). I am setting the maximum to 1838.5 mA (that's Okay) and the motor RMS is 1.3 A (more than 1.2 A). Will these settings overheat the driver?
Will I have any of these problems with the configuration I have set above? Will the TMC2130 overheat?
Update 22 April
My chip is the
TMC2130-LA. Then, to calculate the
Imax = 1.2 A # max current available in the controller Irms = Imax / 1.41 = 0.851 X_CURRENT = 90% Irms = 0.851 * 0.9 = 0.766 = 766 mA # 90% for safety