Stepper Motor Wiring (Screened?)

**pequod** · 01-08-2009

I'm slowly collecting parts to convert my Sieg X2 to CNC.
I've ordered the stepper motors and controllers from Zapp, so no matching problems. The question is - is screened cable necessary to connect the motors to the controllers (4 core bipolar parallel). Working in the electronics industry, I know (a little) about noise in electronics. What I've seen on the you-tube sites, this is not used, or is it taken for granted? Has anyone got views, or experience on this?

**tribbles** · 01-08-2009

I think the amount of current being supplied to the motors, the voltage swings and the speed of signal switching means that screened cable is not really required.

If you were to do high-frequency, low voltage signals then you would need it.

**irving2008** · 01-08-2009

Originally Posted by pequod

I'm slowly collecting parts to convert my Sieg X2 to CNC.
I've ordered the stepper motors and controllers from Zapp, so no matching problems. The question is - is screened cable necessary to connect the motors to the controllers (4 core bipolar parallel). Working in the electronics industry, I know (a little) about noise in electronics. What I've seen on the you-tube sites, this is not used, or is it taken for granted? Has anyone got views, or experience on this?

Some sites recommend it. A lot depends on the length of the cables, the motor current in use and the sensitivity of the electronics around it. For home/hobby use with <2m or cable and typically 2-4A motor current I can't see it being necessary. For longer runs/higher currents I might consider it.

BTW if you do used screened cable, only ground it to the protective ground (mains earth) at one end, to avoid creating ground loops (which can be worse than no screening at all)

**HiltonSteve** · 01-08-2009

I asked the same quesion to Roy at DIYCNC when i collected my parts, he looked at me like I was one of the main characters from dumb and dumber.

This was from a chap that knows his stuff and he said for short lengths of cable that I would be using then no need at all.

**John S** · 01-08-2009

Originally Posted by HiltonSteve

I asked the same quesion to Roy at DIYCNC when i collected my parts, he looked at me like I was one of the main characters from dumber and dumber.

Got to admit Roy can weigh people up well.....................

.

**HiltonSteve** · 02-08-2009

Originally Posted by John S

Got to admit Roy can weigh people up well.....................

.

I asked for that, still laughed my arse of though...:clap:

**Gary** · 02-08-2009

I would alllways suggest to use shielded cable for the motor phases, even though for a home/hobby setup it may not be required.

Why? becasue it is standard engineering practice to shield cables.
From my point of view, it is easier to suggest using shielded cables than spend time on the phone trying to fault find a customers application.

**pequod** · 02-08-2009

Thanks for the replies. I'll be running 4.2A approx 1.5 metres through 3 axis, so maybe it's not necessary. At £3 +VAT per metre, it needs more consideration, or if I can get it cheaper, maybe I might as well.