# Powering a NEMA 17 motor | Wattage Vs Voltage

I apologize if the question is silly as this is my first project involving stepper motors and I'm confused about power supply specifications.

So I'm working on a project involving:

1. 3 NEMA 17 Stepper motors with 4.2 kg-cm torque
2. 3 A4988 drivers

Now the motor is rated for 3.2 V 1.2 Amps/phase. So, at 3.2 V the motors require 3.6 A of current in total which means a wattage of about 11.5 W.

So can I use any power supply which can deliver sufficient wattage or should the power supply be capable of delivering 3 Amps regardless of its voltage?

Is an 18V 2A supply sufficient or do I require a 12V 4A power supply?

• @Joshi, Ah, let me see. (1) Usually the motor current rating is important. So for your 1.2A per phase motor, 1.2A x 2 = 2.4A ~= 4A should be good enough. (2) For A4899, you can use 8 ~ 35V to drive the motor. So, I don't usually consider power! :) See my answer below for motor details. Have a great project. Cheers. – tlfong01 May 1 at 5:13

Question

Which PSU to use for microstepping NEMA17 steppers at 3.2V, 1.2A per phase?