[widgitmaster]

My X-Axis is a bit too heavy for the 144 OZ/IN stepper I have now, it keeps dropping steps at feed rates above 90 IPS! I plan on replacing all the NEMA 23's with NEMA 34's, as I can afford to do so!
Here are the specs on the motor I just got!



Price $99.99 - $118.98 With Shipping
Keling Technology, Inc
http://www.kelinginc.net/

---------------------------------------------------------------
Model: 34H280-45-4A
Nema 34
637 OZ/IN
1/2" Dia single shaft with a flat.
Step Angle 1.8 Deg.
2-Phase
Phase resistance 0.9 Ohms
4.5 ADC/Phase
4.05VDC
4-Wire
A+ Black
A- Orange
B+ Red
B- Yellow
---------------------------------------------------------------

Could someone tell me what size current limiting resistor I should use
for this motor with a Gecko G202 drive?
(I have a 67VDC 6A power supply)

Thanks Guys!
Eric

[JFettig]

go to geckodrive.com and download the manual for it and it will tell you how to calculate it.


either that or just pick the closest value shown on the drive casing (4 amps) and set it as that.

Jon

[widgitmaster]

According to Gecko's manual, the formula is:

R=47*I/(7-I)

I=4.5
R=47*4.5/(7-4.5)
R=211.5/2.5
R=84.6K

Is this correct or does the 4.5 ADC/phase get doubled to 9ADC?

[Evodyne]

According to Gecko's manual, the formula is:

R=47*I/(7-I)

I=4.5
R=47*4.5/(7-4.5)
R=211.5/2.5
R=84.6K

Is this correct or does the 4.5 ADC/phase get doubled to 9ADC?

Your first guess: go with the 4.5 value. The nearest standard value is 82K to which you can add a 2.4K or 2.7K (again, standard values) in series. Have fun!

Evodyne