Just turn the breaker(s) off to the one(s) you're not using. Lock-out plug covers are available also, very common industrial safety equipment. You were also talking about NEMA 3R or 4 enclosures for water resistance, most of those have lockable covers.
An example of the cover I'm talking about (but not the receptacle inside) Note the locking hole on the right side. This is one type of RV outlet
View attachment 136861
As you bring more motors on line, they add together. So the RPC + the Lathe would give you 45 HP of RPC. No problem.
Sorry that picture is so blurry that I can't tell what I am looking at.
Going to need pictures for the rest of it.
Jim, I'll see if I can get a better picture or two. In the mean time, what the heck is this:
On my computer, these display close to the actual size, maybe a hair bigger than 1:1.
I don't know if this is part of this lathe, or just something that got set aside and wound up being forgotten.
To the left of the adjustable wrench, you can see the cover that goes on it. No screws were anywhere around, so they're gone.
Any ideas? I can't tell for sure, but it seems like it mounts with the two hole that go through the body, at either end, and the plunger triggers this switch/relay to some purpose.. The fixture to the left in the first picture and to the bottom in the second seems to be the entry point for such wiring as goes in the thing. I didn't want to spend too much time poking around with it until I know what it is, or if it's even likely related to this lathe at all.
Sidebar: Once upon a time, as a young army mechanic, I was tasked with putting something back together that somebody else had disassembled, but had gotten hurt and was off to the hospital. It wasn't a piece of equipment with which I was familiar, but hey, I'll figure it out, right? So I'm looking at the tray the guy has placed all the clamps and hardware into, and studying the thing, and I saw a long socket-head screw, like 3.8" threads, and I looked at it and looked at the thing, and said: "Hmmm. Where does it go?" I pulled out the manual, went through the assembly and disassembly steps in the manual, and then I looked at the parts manual, trying to find that danged screw. I couldn't find it anywhere in any of the documentation. I looked at an identical machine, trying to figure out where the heck it went. I couldn't find it. Wound up calling the hospital when we found out he was going to be fine, a few stitches, some bruising, and the usual Army dose of motrin later, but I asked him: "Hey, there's this long screw, 3/8 threads, about five inches long, socket head, and I can't figure out where it goes...." He laughed and said... "It goes on [something else.] Just happened to be carrying it in my pocket because I saw one missing and thought to replace it, but put it in the tray when I set my keys and other crap down, digging for something else in my pocket." Lesson learned. It might not be anything at all related to the task at hand.
I was a diligent young fellow though...LOL
By the way, that covered outlet is just the kind of thing I was thinking about. The lock lug is exactly what I'd want. I'd also probably locate it at roughly eye level for me, only because that would mean it would be some time before it would be in reach of youngsters anyway.
Thanks!
Mark