[harryn]

Hi,

I am at the experimenting stage with cnc wood routers and am building up one axis to learn from. At least 2 of my axis will require dual drive setups with 2 motors / axis. For mechanical reasons, I cannot easily tie these dual drive setups together with a jack shaft or belt.

I have a G213V which can output 7 amps, and 1 Gecko nema 34 motor @ 3.8 amps x 12 mH to test and learn from.

I was wondering if it is possible to put 2 of these motors in parallel and drive them from one G213V driver ? (at 3.5 A each)

I understand the potential impacts on the mechanical aspects of the router alignment.

It seems like if the motors start out at a full step position, they would tend to stay synchronized as they pass through full step, micro step, and morphing, but that is just my guess. Any educated opinions about why this will or will not work ?

Honestly, my motivation is budget for the build, but I don't want to destroy a $ 150 driver and a $ 190 motor "learning" that this is a bad idea and everyone already knew this but me.

Thanks

Harry

[fatal-exception]

I had the same question when I built my plasma table, but for the reasons you list, I didn't bother trying it. I just went with an additional G203 and slaved them together through Mach3.

I hope someone can shed some light on if this is possible or not...

Good luck!

Paul

[jhowelb]

Not!

[harryn]

Not!

While I appreciate the thread bump, I was hoping for a bit more of a technical explanation.

[jhowelb]

Get ready for back EMF, burned windings, blown drives and headaches you can't possibly imagine. If it were that simple, no one would market things like Breakout/Motherboard Combo for Gecko Stepper Motor Drivers as seen at PMDX.COM - Products for CNC and motion control applications.

Or the G540 4-Axis Digital Step Drive as seen at Featured Products.

Do your self a huge favor and don't try to "hack the system" for a cheaper product. Folks much smarter than any of us have invested untold hours of diligent study to produce things that work reliably. There are also multitudes that will utilize the "P. T. Barnum" theory to extract profit.

Purchase once, the best product available for your purpose and move on.

Just advice from one bearing lots of "battle scars"!

[boldford]

While I appreciate the thread bump, I was hoping for a bit more of a technical explanation.

Whilst slaving drives is a good solution you may try a series arrangement first if your PSU has plenty of volts headroom. The current rise time will be slightly extended but identical in both stepper motors. Effectively being a constant current source, the chopper will tend to keep the current up to the previous level.

[CoAMarcus]

Not!

While his response was indeed short it is nonetheless correct. A stepper motor drive with midband resonance compensation, like ours have, cannot run two motors at once above 1 revolution per second. The drive will be compensating for both motors at the same time and will send them into violent oscillation.

Your best bet would be to use two drives with two motors and just send those drives the same step and direction signal. If the motors are opposite each other you just need to invert one of the phases and they will mirror each other perfectly.

Marcus

[harryn]

Marcus, thank you for the information. Harry