Problem mit Motorshield

Wir haben ein Projekt mit dem Arduino uno und dem Motorshield von polulu mc 33926 gestartet.
Und zwar wollen wir ein RC- Auto damit betreiben. Wir haben einen Servo, ein paar LED´s und einen 18 V brushless DC Motor. Wir steuern das ganze über eine Fernbedienung (GT4). Unser Problem ist, dass sich der Arduino oder das Motorshield nach ca. 20 sek Motorbetrieb ausschaltet und wir danach nichts mehr ansteuern können. Erst nach Reset lassen sich der Motor und der Servo wieder ansteuern. Dieses Problem tritt nicht auf wenn wir den Motor langsam fahren. Meine Frage ist ob es irgendwelche Sicherheitsvorkehrungen im Shield oder im Controller gibt, die eine Ausschaltung auslösen und wenn ja welche Faktoren dabei eine Rolle spielen. Oder ob der Motor verändert werden muss (wir haben Keramik Kondensatoren vorgeschaltet 0,1mF). Ich hoffe auf eine baldige Antwort und bedanke mich im voraus für ihre Hilfe.

Mit freundlichen Grüßen


We generally can only respond to posts in English. However, I used Google translate to read your post, and it sounds like you are having problems using your MC33926 motor driver shield with a brushless DC motor. The MC33926 motor driver shield was intended to drive brushed DC motors and might not be appropriate for controlling your brushless DC motor. If you are able to continue troubleshooting in English, could you tell me more about your setup? Could you provide more information about your motor? What are you using for your power supply? Could you post pictures of your setup?

- Jeremy

Yeah you are right we want to drive our 18V motor with the mc33296 motor shield. We are using an arduino uno for controlling. We want to run an RC-Car. It is a brushless motor from bosch. Usually it is a motor for an impact wrench. We got problems when we drive our motor full speed. It shuts down the arduino when we give less power. You cant start it afterwards, only with reset of the arduio.
Hope you can understand.

As I mentioned in my previous post, the dual MC33926 motor driver shield is designed to be used with brushed DC motors, and it is unlikely that the driver is appropriate for driving your brushless DC motor. Could you provide a datasheet or link to your motor’s specifications so I could verify if the driver is appropriate for driving your motor?

- Jeremy

I`m sorry there is no datasheet available. Bosch is not willing to tell us which motor they used. We use the PSB 18 LI-2. We researched a lot and we are to 98% sure that they used a brushless motor.

Then you need a brushless motor driver.

We talked to Bosch and they are sure we are using a brushed motor. There are no green ones with a brushless motor.
Can anyone help me please.

Most power tools use far more current than the MC33926 motor driver can handle, so it may be shutting down. Another possible problem is attempting to power a servo from the 5V output of the Arduino – if you are, don’t do that, as the on board regulator cannot supply enough current. Finally, your power supply voltage may be dropping to the point that the Arduino resets.

As Jeremy requested, if you want help, describe how you are powering the system and post a SCHEMATIC DIAGRAM of your setup (or a CLEAR PHOTO of the wiring SCALED TO FIT THE PAGE).

You need to measure or estimate the stall current for the drill motor. There are two ways: (1) measure it directly at low voltage (say 3V) with the shaft locked, and multiply by the motor power supply voltage/3. (2) use a multimeter to measure the winding resistance while slowly rotating the shaft and take the lowest value. The stall current is the motor power supply voltage divided by that resistance value.

If the stall current is higher than 5 amperes, you need a higher power motor driver. I’m very happy with the VNH5019.