Stepper motor specs and drivers - Page 1
Forum section: electronics / projects

author: slowpoke
author_rank: Contributor
timestamp: April 22, 2020, 03:44:51 am
content: I'm trying to use a stepper motor and no idea if i can use this driver.So, i have 57BYG007-04A motor (nema23 size, round, not your typical square), which is rated to 12V and only 0.38A.Coils measure at 58ohm.The driver i hope to use is DM556 with lowest setting of 1.4A.Most motors i dealt with in the past were nema17 3v and 1-2.5A rated and i could drive them with this driver.Thats what puzzles me. High voltage rating and low amps in a BIG motor...Do i dare try ?

author: Paul Moir
author_rank: Frequent Contributor
timestamp: April 22, 2020, 03:59:09 am
content: 0.38A (4.5W) is probably the continuous rating. The thing is you're not going to drive it continuously at .38A; you'll either switch it off or use some less current to hold it in position. The idle current on your driver should be less than .38A and, over time, the average current going into the stepper should not exceed 0.38A or the motor will get too hot and may burn out. But you will need to drive it harder to get it to move fast and as long as you're not overheating it or going ridiculously high everything will be just fine.PS - they lately decommissioned the slowpoke reactor near me. Sad.

author: slowpoke
author_rank: Contributor
timestamp: April 22, 2020, 04:11:01 am
content: This motor, hopefully will run rotary attachment for laser cutter.Its just that i only have this motor and this driver to hand.Can i run the pair ? Motor 12v 0.38A, driver lowest setting 1.4A. Dont care if i blow motor, but i wouldnt want to blow the driver.Here's where i pulled the info on motor (mine is 57BYG007-04):http://www.stepmd.com/reference/57BYG.htm#Edit1# Oh, and the laser cutter motor power supply is 24V. Driver rated 20-50V

author: Paul Moir
author_rank: Frequent Contributor
timestamp: April 22, 2020, 04:21:05 am
content: Yes, the driver current is in peak and the motor current is in average. Driving with 5x the average current is not a lot. The DM556 is coy about what its idle (holding) current is set to but if it's not burning out NEMA 17s then it can't be much.Think of the stepper as a resistor; it'll be fine unless you get it too hot. But you can't be insane and drop 10s of amps through the windings either even if only for a split second or it'll fail in another way.

author: Nominal Animal
author_rank: Super Contributor
timestamp: April 22, 2020, 04:34:31 am
content: The motor voltage rating is just a nominal figure, and basically tells you the minimum voltage you need to get maximum torque out of it.The 0.38A stated looks like the maximum RMS current (so 0.54A peak) the motor can continuously operate at, without burning up.It looks like an unipolar motor (6 wires), similar tothis one. These are often run from Darlington arrays (something like ULN2002A), not via H-bridges or proper stepper controllers.If the black and white wires (or any pair of the six wires) are shorted, you cannot use the DM556 controller, because then the stepper cannot be used in bipolar (4-wire) configuration. If they are not shorted, then you can use stepper in bipolar mode, and the DM556 controller in software configured current mode (SW1:OFF, SW2:OFF, SW3:OFF), with the controller set (using the Windows ProTuner software) to use 0.5A, and SW4:OFF (so standstill current is halved), and preferably microstepping (4 or more microsteps). Even then the motor may overheat eventually.

author: slowpoke
author_rank: Contributor
timestamp: April 22, 2020, 05:02:16 am
content: Driver doesnt have a port for pc connection/config.The left one.The motor is this:White and black wires are isolated, theyre center taps, not going to be used.

author: Nominal Animal
author_rank: Super Contributor
timestamp: April 22, 2020, 06:08:19 am
content: I wouldn't risk it. These unipolar steppers may use very thin wire (and thin lacquer), and the extra heat may cause it to short; I would not bet the driver can survive a short. It might work, but it might also burn your controller.Can't you get a cheap stepper driver controller, like a A4988, instead?

author: beanflying
author_rank: Super Contributor
timestamp: April 22, 2020, 06:29:48 am
content: Depending on your Laser Cutter one of the 'normal' methods of hooking up a Rotary is to unplug the Y Axis motor and plug the rotary into that driver. Some of them do have extra channels to plug a rotary into and 'some' software is setup to calibrate and use them too. Most Lasers run 24V as standard for power supplies and the stepper will within reason only draw up to what the driver is set to. Not enough current it will skip steps in most cases rather than cook anything.What controller/software are you running on your Laser?

author: langwadt
author_rank: Super Contributor
timestamp: April 22, 2020, 10:49:56 am
content: Quote from: Paul Moir on April 22, 2020, 04:21:05 am5x the current is crazy and pointless, more that nominal current only adds a tiny bit of torque and lots of heatthe motor is very high resistance and inductance so it'll be very slow

author: slowpoke
author_rank: Contributor
timestamp: April 22, 2020, 01:01:45 pm
content: Quote from: beanflying on April 22, 2020, 06:29:48 amLaser is run by Ruida RDC6442S, i have Z/U channels free. Z goes for bed lifting (work in progress), U goes for rotary attachment (engraving cyllindrical objects), which is what i expect to use the motor for.Quote from: langwadt on April 22, 2020, 10:49:56 amI dont mind it being slow, it will mostly only move the scanline of engrave.

author: beanflying
author_rank: Super Contributor
timestamp: April 22, 2020, 02:02:47 pm
content: Your Rotary won't pull much current unless you are trying to rotate heavy lumps with Vector moves so I would use it if you have it. There is a 24V curve here for ithttp://www.stepmotor.cn/download/1.8dj/57BYG.pdfIf you keep to just engraving/scan lines I can't see it being a problem unless you stall/jam the drive.The simple option for a test is just plug it into your current Y driver and calibrate the rotary. Set your acceleration and speed fairly low if you are worried