Need some quick help RE gauge wire

[Burn]

Wondering if someone could either give some quick advice here or hop on AIM to talk.

I am heading to Home Depot to get wire to wire up my IMService servos, servo drives and PMDX-122 board. Wondering the following:

What gauge wire is needed to go from the power supply to the servo drives?
What gauge wire is needed to go from the PMDX board to the invividual servo drives?

If anyone can answer those real quick, I am making a trip today to hopefully wire it up by this evening.

Thanks a bunch!

[JerryFlyGuy]

Burn what kind of voltage and amperage are you running through your cables? How long are they? I would think you'd be wanting some shielded cable, can you get that from HomeDepot? Also, some of your wiring should probably be flexible wiring which I'm not sure you'll find at Home Depot either..

[Burn]

The runs from the PMDX board to the individual servo drives are less than a foot and the run from the power supply to the servo drives will probably be between 3 and 5 feet.

With regard to voltage/amperage, the run from the power supply to the servo drive is around 28v DC @ an unknown amperage (IMService's site says 10a maximum). I am not sure at what voltage the PMDX board outputs for a step/dir signal, either. Any advice? Sorry for the lack of information :\

[JerryFlyGuy]

I'd think 16Ga wire would be fine.. you might get away with 18ga as well.. [don't hold me to any of this] Are you sure that Home Depot is going to have the wire you need? I realize they probably have spooled stuff in these sizes but are you sure it's what you want to use to wire your machine? I would think shielded wiring would be prefered for what your doing. It's what I used for mine and it will help elliminate lots of RF and cross talk problems..

[Burn]

Okay, that sounds reasonable enough. I was thinking of shielded wire as well to eliminate cross-talk going from the PMDX to the servo drives. From the power supply to the drives, I don't think I need shielded wire but correct me if I'm wrong.

[Al_The_Man]

One method of limiting EMI from conductors that carry high currents is to run them twisted together, rather than just side by side, this tends to cancel out the radiated field.
Al.

[Burn]

So braiding them together is as effective as buying shielded wire? Cool!

[JerryFlyGuy]

I wouldn't say it's as effective as, but it should help [Al's FAR more knowledgeable about this than I am ] elliminate it between the twisted/braided cables. It won't help elliminate issues w/ cables which aren't twisted in..[at least thats my understanding] I would think that straight DC power cables from the power supply over to the Servo Drives should be ok un-shielded, or just braided/twisted. Everything else should be in a shielded cable however.. Everything which is TTL or low voltage should be in a shielded cable as well. For the most part, if your going to have to buy the cable anyway, you might as well shield it all.. at least, where you can.

[Burn]

Right- Do you think that Cat 5e cable would work well? I can't remember which colors are twisted or not, but if that would work for the run from the PMDX board to the servo drivers I would do that- They're shielded and twisted as far as I know.

[JerryFlyGuy]

generally they are twisted but not shielded. [at least the stuff I bought wasn't] It's about 24awg however, which I think would light up like a lightbulb filiment if you put 28V x 10A through it.. it's made for 5vdc and milli-amp's...

[Burn]

generally they are twisted but not shielded. [at least the stuff I bought wasn't] It's about 24awg however, which I think would light up like a lightbulb filiment if you put 28V x 10A through it.. it's made for 5vdc and milli-amp's...

I would never think of running 10A through that wire, that's why I said going from the PMDX board to the servo drives!

[JerryFlyGuy]

good catch.. it should be fine, however if you start gaining or losing steps, that's where I'd go look. I keep forgeting PMDX is a BOB, everytime I see if it think 'power supply' .. for whatever reason..