On 5/20/2012 11:57 PM, Rafael Skodlar wrote: > On 05/20/2012 12:12 PM, Dave wrote: > >> On 5/20/2012 12:40 PM, Rafael Skodlar wrote: >> >>> I wonder what kind of power and data cables would you recommend for use >>> in X-Y-Z CNC about 1.2mx1m size? Besides power, it's not clear to me how >>> many data lines for sensors, encoders, motor control, etc. are needed in >>> general. >>> >>> Is it preferable to carry power and handful of control signals to the >>> circuit on the gantry and preprocess some functions there or have >>> everything wired into the central box? That would dictate the number of >>> wires in the cable needed and what kind you need to buy. >>> >>> Would cable carrier from McMaster-Carr # 55835K432 be sufficient? >>> >>> Thanks, >>> >>> >>> >> Figure out what cables you need to move back and forth and then choose >> the carrier. Jamming cables into a cable carrier is not a good idea. >> > I'm well familiar with flexing and shielding issues in general since > early HP plotter days. I was hoping to get a simple answer based on real > life experience, get this or that cable with x number of shielded and > stranded or twisted wires ;-) That's why I mentioned size as that would > give one an idea of motor sizes and other requirements. > > Is it better to have one cable with x number of wires to take care of > all needs or a number of smaller cables (y) with x/y wires? > > >> If you don't do some figuring before you know what you are going to carry, >> you will either have too much, or not enough space. Guessing usually >> doesn't work out nearly as well. >> >> > Agree, and that's why I tried to see what others are doing on this issue > as it seem to be poorly documented in general. I try to capture this > from numerous pictures but wires seem to generate little interest in > general. > > >> As an alternative supplier; Igus sells direct in the US. >> http://www.igus.com/default.asp?c=us&L=en >> >> Dave >> >> > Links are always encouraging. However, I'm still struggling with the > variety of cables mentioned on Igus site: data cable, bus cable, servo > cable, control cable. Lots of homework ahead I guess, and that's before > the experiment can begin. > > Thanks guys, > >
I tend to sketch things out on paper in order to maintain my sanity. Generally, motor power cables and encoder feedback cables are separate. If you buy a commercial brushless servo motor setup, they always (so far) come with a Servo power cable that is shielded, and an encoder cable that is also shielded. If you have a gantry machine, you will probably want limit switches and perhaps a home switch on the gantry slide. I would run another cable for that. So that is three cables - two of which need to be run all the way to the gantry motor location. The other motors, if they move, will also need an energy chain tied to them. It all depends on how your machine is designed. If you are just going to use your machine once a week or even a couple of times per week, I'd probably go cheap and try and use Cat 5 patch cables for your signal wires and perhaps your encoders (you can get shielded cat 5 flex cable). If you are going to make money off your machine on a frequent basis, buy the better cables as normal flex cable will eventually break. (Actually they all eventually break, but some last a lot longer than others) Dave ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
