Quote Originally Posted by CraftyGeek View Post
I've been lurking here for a while. I finally got round to starting the build of my CNC Router a couple of weeks ago & I'm flying through it much quicker than I anticipated. I have all the parts that I need except the wiring.

What sort of cable is normally used to connect the stepper motors to the controllers - I assume that it is also the norm to have the controllers nearer the PC away from moving parts, then have the longer cable run from the controller to the motors?

(ultimately the machine will run on 24-28 volts I think, with 3x 2.5A controllers)

Thanks

CraftyGeek
HI, Thi was discussed at length a week ago on Kingfisher's 4x4 [ame="http://www.mycncuk.com/forums/showthread.php?p=8664#post8664"]thread [/ame]and its worth re-read of that thread, but the particular post in question I have reproduced below:


Each driver should be connected seperately to the power supply, do not daisy chain them. An individual fuse in the feed to each driver is a good idea. It should be rated 50% higher than the driver output current - so for motors with a 2A phase running bipolar (4A per phase, 8A per driver) a 12A fuse is a good idea. It doesnt need to be slow blow on the driver side of the power supply. Either chassis mounted fuse holders, or the in-line automotive types will work well up to 16A.

For a 2A phase motor wired bipolar (4A) you need at least 0.5 mm sq per core (typically 16/0.2 wire) - do not use single core house wiring cable, its not flexible and will crack under the vibration of the motor (in time). Ideally it should be screened wire... often you can find this on eBay listed as 4-core CY. 4-core 16/0.2 wire is good for 4.5amps (9 Amps derated 50%), above this you will need to use 24/0.2 wire which is good for 8A in 4-core form (although they are usually derated below this for indistrial applications). example