Cnc wiring!

[Desertboy]

0.75mm 4 core CY cable, you need CY normal 4 core is a big No due to interference. Wire colour is irrelevant and you'll find CY you get 3 blacks wires and an earth. It's very easy to work the wiring out it doesn;t matter how you wire it to the motor the end you wire to the drivers twist 2 wires and try to turn you ballscrew if you feel resistence you have matched pair if not try a different combination. When you have a matched pair the other pair must be matched wire them to the drivers. If the motors go the worng way invert the pin in Mach3/linuxcnc.

https://www.ebay.co.uk/itm/ALL-CY-CA...EdeT991FfFPUNw

Search for companies local to you it's not hard to source cheaper than this.

[Neale]

The CY cable I have used has the three black cores numbered along their length so you can identify which core is which at both ends. The third core could be used for an earth but it works fine as one of the four connections for the steppers - electricity doesn't care what colour wire it runs in!

Talking about awg and oz-in motors suggests that you have been looking at US sites. Europe and European suppliers tend to talk about cross-sectional area (0.75, etc) and Nm. It doesn't really matter which system you use but that's why some people use one set of units and some another.

[Cobey3289]

Thanks guys, it seems to make a bit more sense.
In my research, I've just watched a video of a guy wiring his steppers with
Cy cable. He used a 4 core plus earth and didn't use the earth. He did however expose the wires in his control box and connected them to the side of the metal box to earth them. I'm planning on building a Perspex box, so do I still need to earth the cable or can I just use the 3core and earth as my 4 wires?
Thanks
Mick

[Clive S]

Thanks guys, it seems to make a bit more sense.
In my research, I've just watched a video of a guy wiring his steppers with
Cy cable. He used a 4 core plus earth and didn't use the earth. He did however expose the wires in his control box and connected them to the side of the metal box to earth them. I'm planning on building a Perspex box, so do I still need to earth the cable or can I just use the 3core and earth as my 4 wires?
Thanks
Mick

You need 4 cores to connect the motor to the driver in the control box and use use the screen to connect to the ground star point. Also a plastic box is not suitable it is better with a metal box that can be earthed as it will help with the screening.

You will also need CY cable for the spindle

[Cobey3289]

Quite agree, it seems the more you research, the more questions that end up needing answers!

[JAZZCNC]

Quite agree, it seems the more you research, the more questions that end up needing answers!

Which is exactly why you should never buy anything until you know 100% it's correct for your needs. So don't be afraid to ask.

Regards wiring then it basicly boils down to this for CNC.

Anything which carries signals Ie: Motor wires, Control signal wires, Limit switch, E-stop, require shielded or twisted pair cables. With the Shield going back to Single Earth point " Star point".

Other wires which carry power to components Ie: From PSU to drives, power for control, power fro relays etc can all use normal single core cable often called Tri-rated cable. The cable must be sized according to load it will carry but often people will use one size, that being rated for highest load they'll use. 1.5mm/2 will work for most things.

If using VFD for the spindle then they require special treatment in that shielded cable must be used between VFD and spindle even thou not carrying signals. This is because of the high frequencys they use which can creat lots of electrical interference(noise).

[Cobey3289]

Thanks for that jazz.
Stepper drivers and psu's.
I'm going to be running nema 23's 425oz 3amp. What stepper driver should I use? Some are rated up to 3amp and some more and then they are rated voltage wise. Until I decide on steppers I'm assuming I should hold off on psu's.
I see some people use 2 psu's driving two motors each. Can I just use one for the motors and a 5v supply, or is it best to use one for motors, another lower rated for fans etc and a 5v for the board?

Mick