Help with Stepper Motor and Drivers getting hot

Hello,

I have a Low Current Nema 23 CNC Stepper Motor 1.8A 340oz.in/2.4Nm CNC Mill Lathe Router:

(https://www.amazon.com/dp/B00PNEPKH6/ref=asc_df_B00PNEPKH65364141/?tag=hyprod-20&creative=395033&creativeASIN=B00PNEPKH6&linkCode=df0&hvadid=198072808542&hvpos=1o2&hvnetw=g&hvrand=2726577274206782209&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9007715&hvtargid=pla-350875853183)

I also have a Qunqi L298N Motor Drive Controller Board Module Dual H Bridge:

(https://www.amazon.com/Qunqi-Controller-Module-Stepper-Arduino/dp/B014KMHSW6/ref=sr_1_1?s=hi&ie=UTF8&qid=1518120559&sr=1-1&keywords=l298n+motor+drive+controller+board+module+dual+h+bridge)

What I found is that that the heat shield on the driver gets VERY HOT. I actually ended up burning up one of the drivers (luckily, I bought a 2 pack). I have tried powering the stepper motor with both 12 volt and 6 volt power sources. I need the stepper motor to be functioning for 2 hours; however, it only needs to make 2-4 rotation every minute over that time period. Does anyone have any suggestions for getting the L298N to not overheat or maybe a suggestion for a different driver all together?

P.S. I have read a lot about this problem, but this is my first time working with any of this equipment.

Thank you and any responses are appreciated.

The stepper motors are running at full current ALL the time. Even when not moving, the motors are held in position. If you need this, then adjust the current limit pot on the controller.

If you don’t need motor holding, then most controllers has a pin that disables the controller by pulling that pin low. See if your controller has this and if your Arduino has an available pin to control it.

Paul

A 1.8A stepper needs a proper current-controlling stepper driver, not a DC motor driver. 1.8A is bit high for single-chip
stepper drivers though, 1.5A is about the limit (unless you go to some of the monsters with huge
heatsinks).

Have a look at the specs for the DRV8825 for one of the go-to single chip stepper drivers.

Yes, the motor and driver will be hot.

While I have no personal experience of them there are driver boards that use the Toshiba TB66xx and TB65xx chips that claim to be able to control up to 4.5 amps.

...R

Those are the monsters with huge heatsinks - still about the same on-resistance as the others I think - only
discrete MOSFETs give you on-resistances in the milliohm range, which is how to drive large steppers without
needing large (or any) heatsinks.

Hi,
From the site you linked to;

Product description
This bipolar Nema 23 stepper motor with 1.8 deg. step angle (200 steps/revolution).
Each phase draws 1.8A, allowing for a holding torque of 2.4Nm(340oz.in).

Electrical Specification:

  • Manufacturer Part Number: 23HS41-1804S
  • Motor Type: Bipolar Stepper
  • Step Angle: 1.8 deg.
  • Holding Torque: 2.4Nm(340oz.in)
  • Rated Current/phase: 1.8A
  • Phase Resistance: 2.75ohms
  • Inductance: 17mH+/-20%(1KHz)

Physical Specification:

  • Frame Size: 57 x 57mm
  • Body Length: 104mm
  • Shaft Diameter: 8mm
  • Shaft Length: 20.6mm
  • D-cut Length: 15mm
  • Number of Leads: 4
  • Lead Length: 500mm
  • Weight: 1.5kg

Connection:

Black(A+), Green(A-), Red(B+), Blue(B-)

Warning:

Make sure the motor connect to a constant current or chopper drive controller before you test motor.
Connecting the motor directly to a power supply will destroy the motor.

The resistance of the coils is 2.75Ohms
With a 12V supply your load on the driver is 12/2.75 = 4.36Amps

You need a current controlled driver for that stepper.

Tom... :slight_smile: