New to CNC

[WalkerYYJ]

Hi all, sorry as I am sure this is a silly question however I am considering getting a G540 to replace a semi functional TB6560 ebay board I picked up the other week.
The package I originally ordered came with 4x Nema 34 (8 wire 2amp) motors. (34HST9805-37B2)
and a 24V power supply

4 Axis Nema 34 stepper motor 878oz.in CNC Router/Mill - eBay (item 190504477644 end time Apr-21-11 19:29:20 PDT)


Would the motors be an acceptable match to the G540?
I was planning on eventually upgrading the power supply to something a bit beefier but before going ahead and putting an order through for the G540 I wanted to make sure the setup would work/not be a silly idea etc...


Planning on using Mach3 as the primary software.

Any and all info is appreciated!
thanks!

[ger21]

To get maximum performance from those motors, you'd need to supply them with 120V. The G540 can only handle 50V. Most likely you'll be limited to very low speeds. You should be looking for motors with an inductance of around 2.5mh.

The formula for optimum power supply voltage is 32* square root of inductance.

[morestuff]

If these motors were wired for parallel operation, the inductance would be about 3.9 mH and the current required for full torque would be 4 amperes. My guess is that the trade off of running them at 3.5 amperes instead of 4 amperes would be more than compensated for by the lower inductance and that real world torque at speeds typically used would significantly improve.

Regards,
Steve Stallings
PMDX.COM - Products for CNC and motion control applications

[WalkerYYJ]

Originally Posted by morestuff If these motors were wired for parallel operation, the inductance would be about 3.9 mH and the current required for full torque would be 4 amperes. My guess is that the trade off of running them at 3.5 amperes instead of 4 amperes would be more than compensated for by the lower inductance and that real world torque at speeds typically used would significantly improve. Regards, Steve Stallings PMDX.COM - Products for CNC and motion control applications

Do you think I could get away with reasonable performance using these motors in parallel with a G540 then?

Would 50V be a the minimum?

[morestuff]

Originally Posted by WalkerYYJ Do you think I could get away with reasonable performance using these motors in parallel with a G540 then? Would 50V be a the minimum?

Yes, I do think you would get reasonable performance running
these motors on the G540 as compared to your old board. You
should get (3.5/4)= 0.875 of the rated torque of the motor.

While higher voltage will result in faster performance from the
motors, 50 volts is the MAXIMUM rating of the G540. If you
really want to push these motors as far as they can go you
could spend more money and use G203V individual drivers
and a breakout board.

Regards,
Steve Stallings
PMDX.COM - Products for CNC and motion control applications