Hello, I am using an adafruit motor shield v2.3 with my Arduino Uno to controle two stepper motors. I bought a Polar Hpada 18 W 9 V 2 A charger power supply. I was able to controle the first Nema 14 stepper motor. But the nema 17 is not working properly, and at some point the "power" led on the arduino stops for few seconds and then start blinking. Do you think I need more power supply? It will not damage the nema 14? Sorry but I am not familiar with that. On the Nema 17 I am not able to see any voltage requirement, you can see that on the uploaded table.
9 volt is likely too little. 12 or 24 volt would do better. Check the driver board data for its limits.
You cannot use this stepper with your motorshield. This stepper needs a current driver. The 'adafruit motor shield v2.3' can only be used with voltage driven steppers (steppers with a high rated voltage). See also this page of Adafruit about compatible steppers.
Thank you for your answer. Do you think this stepper would work? Or do you have an example of a compatible stepper?
No, as you can see from this data in your link:
Nominal current / phase: 1.50 A & phase resistance: 2.3 ohms.
That means the rated voltage of the coil is only 3.45 Volt. That's an example of a stepper where the obove linked page of Adafruit warns:
A Voltage rating is often stated. It is usually calculated from the two above - but not always. It is better to calculate yourself from the above parameters using Ohm's Law.
E.g. this seems to be a suitable stepper ( from its electrical data ). It has much less rated current and a higher coil resistance.
Thank you very much, now I understand the problem. I tried to find another stepper with more Ncm then 26 but without success. Do you think this is the maximum holding torque for stepper with small current value?
Match the 2 Amps as in the data sheet, resistance is 1.4 Ω
So you do understand that you have to change the shield instead of the stepper motors.
That shield is basically a brushed DC motor driver board, not a stepper motor board.
Because of that only some stepper motors will work.