g540

[Scooby Doo]

I was wondering if the amps of the G540 would be sufficient enough for a machine that is 72 x72 using 495 oz steppers (2 on X and one on Y). I have larger explaination of the machine in the JGRO forum.
Any and all help is appreciated

Thanks,
Scooby

[CoAMarcus]

If you could post the specs of the motors that would help out. You can't tell a whole lot from oz/in. and table size. I would need to know specifically the voltage, current, and inductance of the motors on your table.

Marcus

[sawmiller]

hey marcus,
i clicked on the lil gecko spot up above, doesnt go to the website like i think it should.thought you might want to know


if i get the G540 i plan on using it with keling's 425 oz/in motors
KL23H286-20-8B
4.17 v
2.8 a
6.8 inductance.
at least untill i get the cash for some 201's

now i realize that with that inductance it wont be the best, but
will it drive them better than a set of chopper drives from pminmo
at 38 volts ?
dan

[CoAMarcus]

Dan,

The G540 will run that motor just fine even with the high inductance. Because our drives are pulse width modulated they will run much quieter than a chopper drive, so the answer would be yes.

Marcus Freimanis

[Crevice Reamer]

To get the fastest rapids with the 425s, you would need an 83 volt power supply. I can get 350 IPM on my SX3 with 72 volts and G203Vs.

However, the 50 volts able to be used with the G540 is WAY better than the 24-36V available for the other cheap drives.

CR.

[Scooby Doo]

Thanks for the advice, I will probably go with the larger power supply. I am making one change to the lineal motion, that I believe will help the motors. I am going to be using a rack and spur gears for the the X and Y. My theory on this is that there will be less power needed from the steppers if they are not having to pull/push from 72" away. Is this a valid theory or am I all wet?
Thanks again and any
Scoob

[Scooby Doo]

I meant to end that reply with "Thanks and any further advice that you have to give will be welcomed"

[ViperTX]

Originally Posted by CoAMarcus Dan, The G540 will run that motor just fine even with the high inductance. Because our drives are pulse width modulated they will run much quieter than a chopper drive, so the answer would be yes. Marcus Freimanis

Okay Marcus....now, I'm totally confused. In the Cheap Drives thread, you stated that the inductance had to be below 3mH. So, what did I miss? I'm getting ready to order the Keling (sp?) 4 axis kit for use on an X3.

Paul

[CoAMarcus]

Paul,

The 3mH recommended inductance is to get the best performance out of your motors. The G540 will run those but not as efficiently as a higher power drive would because of the high inductance.

Marcus

[Crevice Reamer]

Originally Posted by ViperTX I'm getting ready to order the Keling (sp?) 4 axis kit for use on an X3. Paul

Hi Paul.

The X3 needs a N34 motor for the Z. Currently available N34s pull about 6 amps. Until some lower amp/volts N34s are available, the G540 may not be the best choice.

CR.

[devincox]

what about these:
http://stepper3.com/shop/stepper3-12...hase-p-88.html

STEPPER3 1200 OZ-IN 4 WIRE 3A/PHASE
NEMA 34

[Crevice Reamer]

That would be a huge amount of money wasted on very poor performance. The 22 mH inductance would rule these out even for the G203V, let alone the G540.

CR.