What kind of power supply

does anybody know how many volts and amps my power supply would need to be for 4 nema 17 motors rated at 2.4v and 1.5 amps per phase? i am also using a cnc ahield with drv8825 drivers. i am currently using a 24v 5 amp power supply. also when reading the voltage from the driver with a multimeter it reads 24v and i cannot lower it when turning the screw on the 8825. can somebody help me please

Hello.

A 24V power supply that can provide up to 5A of output current should be capable of running those motors. Where did you get your DRV8825 carriers? The VMOT voltage being shorted to the VREF via is a known problem of one of the knock-offs of our carriers, as discussed in this RepRap blog post. If you are not sure if your boards are genuine, you can post a picture of them here.

Additionally, if your CNC shield is meant for the A4988 carrier, you will probably need to use the wiring diagram shown in the “Key differences between the DRV8825 and A4988” heading at the bottom of the DRV8825 carrier’s product page to make it compatible.

-Nathan