Arduino Forum

Topics => Robotics => Topic started by: altronic on Dec 06, 2017, 07:16 am

Title: Nema does not work correctly.
Post by: altronic on Dec 06, 2017, 07:16 am
My power source is a 16v 2.5 A, set up with a variable voyage regulator. And an Arduino Uno and a motor shield with 3 shift registers (74HC595N).
Using 12v on the Nema 17 I get very sporadic results in rotation of the motor. The sketches are from the Arduino ide library. Any help would be appreciated, Thank you.
Title: Re: Nema does not work correctly.
Post by: altronic on Dec 06, 2017, 07:51 am
I read the data sheet for ic, and it looks like they are rated for 3v to 6v. But I have a 5v stepper motor and get the same results, sporadic rotations if any at all.
Title: Re: Nema does not work correctly.
Post by: Southpark on Dec 06, 2017, 10:10 am
But I have a 5v stepper motor and get the same results, sporadic rotations if any at all.
Check how much current your 12 volt regulator is able to deliver ...eg. maximum current from the manufacturer specs.

Try using a stepper driver like DRV8825.
Title: Re: Nema does not work correctly.
Post by: altronic on Dec 08, 2017, 02:28 am
South Park I think you are right about trying DRV8825. But wouldn't have though my 12v regulator would decrease the amps. I'll call it a wall wart rated at 16v/2.5 A and I run the through the 12v regulator, I guess the amps would be reduced, but by a very little amount. But I'll have to check out the data sheet for the regulator. Thanks for your answer. I'm sure you are right.
Title: Re: Nema does not work correctly.
Post by: PaulS on Dec 19, 2017, 08:29 pm
Quote
I guess the amps would be reduced, but by a very little amount.
Stopping guessing, and start measuring.
Title: Re: Nema does not work correctly.
Post by: shooter on Dec 20, 2017, 02:07 pm
More info on the shield is needed, so what type are you using?
how many amps can the shield handle, what is the speed you are stepping try 10 steps /second.
Title: Re: Nema does not work correctly.
Post by: MarkT on Dec 22, 2017, 10:10 pm
My power source is a 16v 2.5 A, set up with a variable voyage regulator. And an Arduino Uno and a motor shield with 3 shift registers (74HC595N).
Using 12v on the Nema 17 I get very sporadic results in rotation of the motor. The sketches are from the Arduino ide library. Any help would be appreciated, Thank you.

Most steppers these days are low impedance motors that require constant-current drive from a chopper-style stepper driver, not a DC motor shield.  Such motors have winding resistances of an ohm or two and if connected
to 12V will burn something out quickly.

But you've given no details about the actual motor itself, and you need to post full details of all the hardware if people are going to figure out what's happening.