G540 Questions

[Puppetworks]

I just received my G540 by FedEx. Very exciting. I've had my steppers for months and finally my Sherline mill conversion is on the move again. The motors I bought on eBay the specs are as follows:

Technical Specifications

SOC Part No.: SM3016B

Frame Size: NEMA23

Step Angle: 1.8 degree

Voltage: 3.0V

Current: 3.0 A/phase

Resistance: 1.0 Ohm/phase

Inductance: 1.6 mH/phase

Holding torque: 13.5 Kg-cm 183oz-in

Rotor inertia: 480 g-cm2

Detent torque: 0.68 kg-cm

Number of wire leads: 6

Weight: 2.20 lb (1.0 kg)

Length: 2.99” (76mm)

Shaft: SM3016B - Double ended, ¼” dia.


As I read through the User Manual that came with the drive it states that one should choose a motor with rated current of 3.5A or less and that has a rated winding inductance of 2.5mH to 3mH if maximum power output (>100W mechanical)is a requirement. Does the lower inductance of the motors i have present a significant problem?

I'm fairly sure I've done the math right to determine that i need a 40v power supply to get the maximum speed from these steppers, but I'm unsure of the current I'll require. Do I multiply 3A for one phase by 3 since it's to be a 3 axis system? resulting in a 5.4A requirement?

Is a fan cooled case a necessity with this drive? The manual states no heatsink needed below 40C.

I'd really appreciate any help, guidance or corrections.

thanks,

-Hephaestus

[ger21]

.......... but I'm unsure of the current I'll require. Do I multiply 3A for one phase by 3 since it's to be a 3 axis system? resulting in a 5.4A requirement?

Last time I checked, 3x3 = 9.

A 6 amp power supply should be fine.

[Puppetworks]

Thanks Gerry, I believe that's my last hurdle of discovery before constructing my power supply. I'll be hunting down parts in the next few days. I am rather concerned about the motors I have having an rated winding inductance outside the recommended range of the G540. I don't know if this will cause me significant issues and if it will, if they're issues I'm prepared to live with. I'd really like to get this sorted before I get too far into construction of my PSU, just in case i have to replace my steppers.

Thanks again Gerry

Any advice on the remaining issue would be greatly appreciated.

-Hephaestus

[ger21]

I don't believe the lower inductance will cause any problems. You might want to call Gecko, or ask on their Yahoo group (Geckodrive) to be sure.