Hello I have a arduino mega that’s hooked and running 7 ddrv8825 drivers and 7 nema motors that have 1.7amps rating I was wonder what type of power supply do you guys recommend? Also the way it works is one nema motor turns then stops then another turns then the first one turns again then another motor turns then the first etc for 6 times so only ones constantly one also I have a lil 4x20 lcd the cheap blue one on it and a hx711 all basically hooked on a bread board so far I’ve ran only two nema motors on a 3 amp plug and then arduino mega on another plug I believe 3amp too and works good but I’m adding the other 5 motors. I was thinking something like this
NEWSTYLE 24V 15A Dc Universal Regulated Switching Power Supply 360W for CCTV, Radio, Computer Project https://www.amazon.com/dp/B01CS5G8J6/ref=cm_sw_r_cp_api_i_vQd8AbCK1ZM7B
Steppers take full current whether moving or holding position (unless explicitly switched off, which means they can be turned easily and you lose position).
So 7 steppes @ 1.7A = 11.9A. Times 1.5 for safety (power supplies often can not supply the full power for long, they'll get really hot) makes for an 18A supply.
The rest doesn't need much power, and can piggyback on the main supply. Do isolate your control electronics properly from the noise of the motors, particularly the power spikes from switching on/off the coils.
[EDIT: see replies below; this is a gross overestimation of the power supply current required by the steppers as it's regulated by the stepper controller]
wvmarle:
The rest doesn't need much power, and can piggyback on the main supply.
Note that 24V is outside the range of the Arduino power input (20V max, 12V recommended max). You can get around that by adding a 5V buck converter to supply the Arduino with 5V from the 24V supply.
Are your NEMA 17 motors rated for 24V? Stepper motors should have a voltage rating as well as a current rating.
Current limiting stepper motor drivers act as switching voltage regulators, so the current drawn from the power supply can be substantially less than the motor current.
You MUST set the DRV8825 driver so that the current is limited to 1.5A or lower.
Post a link to the product page for exact stepper motor you have (or to the data sheet) and we can help you further.
I missed the 24V part. That indeed needs a buck converter, which should provide quite good isolation from the motor noise in the process.
To calculate the power supply requirement you need to know how many watts are required by each motor and as you have not told us the motor coil resistance we cannot work that out.
Post a link to the datasheet for the stepper motors.
...R
Stepper Motor Basics
Simple Stepper Code
Stepper Motor Nema 17, 3 PCS Nema 17 Stepper Motor 4-lead 1.8 Deg 40N.cm Holding Torque 1.7A 42 Motor for 3D Printer Hobby CNC Router XYZ By Beauty Star https://www.amazon.com/dp/B0716S32G4/ref=cm_sw_r_cp_api_i_Sqk8AbG713MS0
That’s the stepper motor I’m using
Would this work the it does 20a at 12v
Padarsey 12V 20A Universal Regulated Switching Power Supply Driver for LED Strip Light CCTV Radio Computer Project https://www.amazon.com/dp/B06WPBF494/ref=cm_sw_r_cp_api_i_7uk8AbA1C0CCQ
Or if you guys can recommend me one. I was thinking of just wiring it to the motors cuz idk how I’d wire it to arduino unless I bought a lil converter but I’d rather not and just buy the psu for running the motors
wvmarle:
Steppers take full current whether moving or holding position (unless explicitly switched off, which means they can be turned easily and you lose position).
So 7 steppes @ 1.7A = 11.9A. Times 1.5 for safety (power supplies often can not supply the full power for long, they'll get really hot) makes for an 18A supply.
The rest doesn't need much power, and can piggyback on the main supply. Do isolate your control electronics properly from the noise of the motors, particularly the power spikes from switching on/off the coils.
Padarsey 12V 20A Universal Regulated Switching Power Supply Driver for LED Strip Light CCTV Radio Computer Project https://www.amazon.com/dp/B06WPBF494/ref=cm_sw_r_cp_api_i_7uk8AbA1C0CCQ
Wb that one
Slow down a bit.
Give us a chance to respond to a Reply before posting another one about the same thing - or wait until you have made up your mind before posting a Reply.
Referring to Reply #6, the motor has a 1.5ohm coil resistance which, with 1.7 amps, implies 4.3 watts - say 5 to give a margin of error. So 7 motors would require about 35 watts. I would go for a 70 watt power supply which implies 6 amps at 12v or 3 amps at 24v.
Obviously a power supply with more amps would be fine.
...R
I second 3 amps at 24v.
You will get faster stepper motor response from the higher voltage power supply.
jremington:
I second 3 amps at 24v.
You will get faster stepper motor response from the higher voltage power supply.
So I’d only need say 3amps with 24v to run all 7 motors?
So I'd only need say 3amps with 24v to run all 7 motors?
That is what several posts have now tried to explain to you. What difficulty are you having to understand this?
Daltonk:
So I’d only need say 3amps with 24v to run all 7 motors?
Yes. I was miscalculating by using the rated amperage of steppers (like you'd do with regular motors).