Re: CMD-260 test mode?

Hi Jeff,

#1 check the mfr's recomendations. do not exceed either the amps or
the volts. you can damage the drivers with too high of either.

#2 higher volts = faster speed

my coraollary :
Better drives $$
Better steppers $$
seeing what you have now, work - PRICELESS !

#3 half winding = full nameplate amps - hotter motors.
series winding = half nameplate amps - less rapid speed.

If you use the series, you limit (reduce) your rapids speed.

The series will let the steppers run cooler. for my ap's I cannot
get high speeds as the 486-66 I have is limited to about 11,000 hz.

If you already have a 28 volt power supply, use it. try it out.
better to see stuff work and KNOW what you want to change than shoot
for the moon and have problems.

If you just want to keep the amps low to get started, use the series
winding. if you find you need faster rapids, then you will know the
difference. if you are comfortable with parallel or half coil or
only have 4 wire steppers, use the higher amps (nameplate or max of
drive, whichever is lower.)

If you use lower voltage and want more speed, you will know what
higher voltages will offer.

Many of us start low and work our way up. espically first timers.

Hope that helps.

Dave







--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Jeff Goldberg" <jeff@w...>
wrote:

>
> Thanks for getting back to me. My concern is that I've tentatively
> identified the NEMA 42's as having a nominal voltage of 2.1 volts

and a

> current rating of 9 amps. According to the white paper on Gecko's

site,

> they recommend that the voltage be kept to less than 25 times

nominal to

> prevent motor overheating. I figured the 28 volts I was going to

use was 10

> times nominal rating and I'd pump up the amps to the drive limit (8

amps).

>
> Half of the advice I've gotten off the chat group has told me to

run the

> voltage low and use half winding and keep the current low. Half

the advice

> is to run balls out on both voltage and current. A third half is

telling me

> to raise the voltage above the advice Gecko (I'm using CMD-260,

from a Gecko

> competitor, but I assumed the advice was generic) is giving and run

the

> current low.
>
> I've rebuilt the power supply three times in the past week and I'm

all

> confused.
>
> Jeff