Chaps,

Mulling over the option of putting my control box into my 19" rack with the servers, I think I have a snag with that, but could use an opinion:

I was intending to run a seperate 32A RCD spur for sole use of the CNC machine and all its electronics (including the PC that will run Mach3). Taking the advice above, if I run all the shielding and earth points back to a star point in the 19" rack mounted case and then onto the 32A earth feed, am I creating a ground loop with the existing 15A feed's earth supplying power to the existing rack mounted windows servers via two rack mounted distribution bars? i.e earth will have two paths back to the consumer unit 1. through the 32A spur's earth and 2. through the 15 Amp ring's earth?

If that's the case I see a few options:

1. Buy a new control case (not a problem but does mean I use some valuable workshop/office real estate
2. Use the existing rack mount server case but isolate it from the rack, so that the two earth paths (15A and 32A) are seperated - tricky to do, as the case is bolted to it rails and hence the 19" rack itself.
3. Up the rating on the 15A circuit and run the servers and the CNC off of the same circuit - risks dirty power to my precious data/server hardware
4. Stop drinking Redbull at night and conjuring up problems where they might not exist ;-)

I'm about to order the shielded cabling, e-stop button, limit switches this weekend, so any help would be most appreciated, as I can add a new control box to the order if its needed.

BTW - what do you guys normally use for limit switches - RS has some pretty exotic looking kit, but if I can use a suitably rated momentary single pole then I'm all for shaving a little cost.

Cheers


Chris