Re: wire for motor ?

--- In CAD_CAM_EDM_DRO@yahoogroups.com, cnc002@... wrote:

>
>
> In a message dated 12/10/2006 1:00:24 PM Eastern Standard Time,
> washer@... writes:
>
> No.. you've made a common mistake. Wire has a given resitance per unit
> length. This resistance will cause a heat buildup in the wire when

a current flows

> through the wire. This is why wire is rated by it's current

capacity (see

> any wire chart).

Interesting. Can I then assume that a 3 amp chopper will deliver a
constant 3 amps to the motor ? and therefore size the wire for 3
amps ?

I can see that in a holding posistion, with the driver holding one
phase at full power (full step) the wire would experiance the highest
amp load. any microsteps would reduce the full load to some portion
of full.

In looking at the AWG charts the first thing that does not make sense
is the 14 and 12ga wire. I had always assumed 12ga in a residence was
good for a 20 amp servcie and 14ga was good for 15 amps.

The AWG chart shows 12ga as good for 9.33 A and 14ga as good for 5.87 A.

Dave