Electrical grounding

My DSP 1060 machine calls for a proper ground connection direct to a ground rod, not a water pipe or conduit. I’ve got a ground rod in the corner for my CNC milling machine and it’s hooked up to that for now.

How important is the grounding wire length and gauge? I’ve just run 14 gauge MTW for now since that’s what I had a lot of on hand. Should I be using a heavier braided grounding wire?



Why wouldn’t you use the ground wire on the AC power plug for the laser?

Mine said the same thing… I just rely on the AC ground. It’s common to the chassis / grounding lug of the machine.

I think it is best practice not to have a secondary ground rod for a branch circuit from your already well grounded panel.

I’m not worried about what my Chinese machine specified. Similarly, i sure as hell didn’t trust, use, or maintain any of the wiring to those universal outlet fire traps on the machine. Lol.

The grounding post is for two-wire AC installations common in Asia.

You should have all your machines at the same ground potential - pump, air, extractor and laser. Check your chassis and all components against the centre-pin of your power plug.

You can use the ground post for ensuring your water reservoir is at the same potential.

The manual for my US-made CNC milling machine has a page and a half devoted to proper grounding, with ground rod specs and wire gauges listed, and dire warnings about voiding the warranty if it’s not independently grounded close to the machine.

TREE MACHINE TOOL CO., INC. requires a separate “ground electrode” for grounding its machine tools. Maximum Permissible ground resistance is 5 ohms. Ground rod placement should be at a point as close to the machine as possible.The machine tool should not be grounded through its own conduit.

From a quick look around online it sounds like this is pretty common, and a source of contention since you’d normally have a single ground point. If the laser doesn’t really need an independent ground, then I won’t worry about it.

And no, I don’t use any of the universal outlets on the machine. Wiring issues aside, the machine is running off a 240v transformer and the chiller wants 120v. If I could change the voltage for the chiller, I’d just run the whole setup off of 208v (still in spec for the laser) and skip the transformer, but I’ve got the cabling all run overhead and running a separate AC line for the chiller would require another hour on the ladder.

“Tree” were an industrial clearing house - their CNCs were made by Kao Ming

Not my Journeyman 325, as far as I can tell. Nameplate says it was made in Racine, Wisconsin. From what I’m seeing online maybe the later machines under the Tree name were imported, but I don’t see any sign that this was made overseas.

If your journeyman is CNC, that’s a retro-fit, isn’t it? How old is that machine - certainly older than the last two or three decades.

I guess I should have qualified that - Tree as a manufacturer is now a clearinghouse. Their current machines are made by Kao Ming.

The requirements for grounding a machine that draws quarter of an amp, are much different to those requirements for a machine drawing 10A.

Not a retrofit. It was built in 1989 with a Dynapath Delta 20 CNC. Sounds like maybe they sold off the name at some point, like Westinghouse?