Whole Shop And Machine-specific Help For Dunce

markamerica

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Hi everybody! Here's the link to my thread in the beginner's section in which I purchased a lathe. This should provide some reference as to what's gone on to date. To start, I guess I should state what my shop's electrical status is. Years ago, when we moved to our property, there was nothing more than a water meter out at the edge of the right-of-way. Everything we needed, we would have to build/buy. We threw a no frills double-wide on the property, and to hook it up to electric, it was going to require Oncor to install three poles across my pasture. That was going to cost, but one pole was "free" because they had to hop the highway, so that was covered, and then the second one was covered by the new service account(they were willing to add one "free" with a new account.) Since that would mean I'd have to buy a pole, and since we were leveraged to the hilt at the time, (still owning our old home, which we shortly thereafter sold,) and since we had poured so much into building fences, putting in thousands of feet of water line, to service the house and the horse pastures, I had to come up with an idea. The thing was, I said: "We want two service accounts. One for the house, and one for the barn we're going to build." That got us the "entitlement" in their system to get that third pole "free." For a long while, it powered a yard security light. Then, sick of paying the service fee for the second account, my wife discontinued service. When we built the barn, we got to that point where we were out of money to go further, which included things like enclosing my workshop, and a storage area. I had installed a load center, wired it up to the little service pole in the barnyard with a safety disconnect and a meter base. Unfortunately, the limitations will always be single phase. I can't get 3 phase, any flavor, so this has created a problem.

I'm going to need to buy a phase converter. I've read all sorts of opinions on the issue, and I have at least a grasp of the issues involved. Here's the deal: The lathe I just purchased has a 15HP motor. Whether the motor turns out to be bad and a replacement is necessitated, I'd just as soon anticipate the 15HP-class electrical load. Eventually, I expect there will be a 3 phase air compressor, and a 3 phase milling machine, in addition to this. I can't think of anything else (at least for the moment) for which I'll need 3 phase. Maybe someday, a surface grinder???

I have another problem, which is back when I installed the load center, and etc, I basically went with the cheapest thing I could get away with. 100amp meter base, 100amp safety switch, and 100amp load center.

That was a mistake. I should have just spent the extra dough at the time and bought 200amp equipment. Since I knew I wouldn't be wiring anything up immediately anyway, I went with the cheapest I could to get what I needed.

Enter the 3 phase discussion. I've been looking at Rotary Phase Converters. Based on what I have to spend, and what I have to power, I'm thinking this is my best bet. For the class I'm looking at, a 60 amp single phase requirement is needed. So you see my dilemma: That will already suck up 60% of the capacity of my load center, etc. So what I'm thinking about is changing out to 200amp gear, now, before it gets harder to do...

Thoughts?

Thanks!
 
The other issue in this thread revolves around the lathe I've purchased. It's a 1979 Martin DLZ, and its electrical is either absent or shot. Basically, I'm going to need a new enclosure, a new motor, new switches, new wiring, and new everything... So where to start... Let's assume that I will need a new motor. Looks like a 254t frame 15hp motor should do the job. (As near as I can tell, this is what the existing, probably bad, motor is...) The single difference is that the existing motor, the end of the shaft is threaded for a screw of 5/8" diameter. I haven't pulled the belts and all just yet, but I'm wondering: If that's the mechanism for holding the pulley on, I don't find motors with threaded shafts. They all just seem to have a center... No threads. Ideas about this? Can I get a different pulley and secure it by other means? Thoughts?

Thanks!

Mark
 
Consider that the RPC will only draw a fraction of its motor's rated current when running. The starting load is pretty high but in some cases the power factor correction may actually cause your electric meter to run backwards when it's idling. Also concider that the lathe will be pretty much idling most of the time also, it rarely will be anywhere close to running full load.

The first thing I would do is run the lathe motor over to your local motor shop and get it checked out.

As far as pulleys go, I like the various taper lock types. Available from many vendors
taper-lock-pulley-1418156.jpg

The threaded shaft is somewhat common on European motors, I have seen it before. You will just have to take a good look to see how the pulley is attached.
 
Well a couple things, I agree with Jim in that most of those large frame motors can be re-furbished for much less than replacement. We used to re-furbish most if not all the motors rather than replace them and these were on macines wore out to the point of needing ways re-surfaced, lead screws re-cut or nuts made to fit. so before I gave up on what you have I would have it looked at. As far as phase converters I would contact the people at American Rotary, they are near me and I know several people who use their product with good results and they offer free tech support to help you figure out what you need. Once you determine how much power you need for your converter, its then determining how many large draw machines will run at one time and then adding your load for wall sockets and lighting to determine your total need. I am not an electrician but that is exactly what a friend, who is one, did for me to determine what I needed to put in my shop. Remember a big panel can always have more power run to it, changing out the panels is a project that takes time which =$ if your paying someone.

https://www.americanrotary.com/
 
Jim,

Yes, I was looking at pulleys like that last night on ebay. By the way, people will notice I mention ebay a lot. The reason is because sometimes, I'm in an area a bit over my head, and ebay helps educate me. They have almost "one of everything" in the broadest sense, meaning when I'm trying to figure out the proper name for a thing, or the proper thing in any respect, as a searchable database for all sorts of things, it's actually a good way to figure out what I need.

As for the RPC, you're quite right, based on my reading. I find that if I get an RPC of the right size, so long as I'm not starting multiple pieces of equipment simultaneously, but merely running them simultaneously, the RPC I need is a good deal more economical. I'm looking at a 20hp unit that will start up to a single 20hp device, but in the aggregate, can run up to 60hp of equipment. It's PROBABLY more than I'll ever need, but you already know my thinking on that. I know I'm going into this with a 15hp motor, so I'm giving myself a smidge of excess capacity.

TakeDeadAim, Thanks! American Rotary is one of the brands I've been looking at. Back when we built the barn, I was going to be happy to have basic power to it. Over time, it became clear that I'd need to rethink some of this before putting another $1 into it, precisely because it's a lot harder to add capacity later. So that's why I'm looking at it, and doing a real budget on what maximal loading I'm apt to ever want. When I start adding things up, light, etc, standard 20 amp wall outlets, yada yada, it adds up fast. Good news is that there's only so many things I can do/run at once. That's the natural limiter for me.

Thanks!

Mark
 
The single difference is that the existing motor, the end of the shaft is threaded for a screw of 5/8" diameter. I haven't pulled the belts and all just yet, but I'm wondering: If that's the mechanism for holding the pulley on, I don't find motors with threaded shafts.
Do you mean that the end of the shaft is drilled and tapped for a 5/8" screw or that the shaft itself is threaded?
 
My shop is supplied by a 50 Amp breaker to the sub panel. It has 14 20 Amp quad outlets, my router system (4.8KW), 5HP air compressor, mill (3 HP), lathe (3HP), 300 amp welder, and all the other stuff. Obviously if I fired everything off at the same time the main breaker would trip. But there is only one of me and I can only run one machine at a time, or sometime two. The base load in the shop is about 3 amps, from the battery chargers, idling VFDs, small refrigerator, and other small stuff. All of the lighting combined is about 10 amps, but I normally only turn lights on in the area that I'm working.

What I'm saying here is you don't have to supply power the the shop with the idea of loading up everything to the max. With a 100 amp service you should get along fine unless you are planning on running a full production shop.
 
J
Do you mean that the end of the shaft is drilled and tapped for a 5/8" screw or that the shaft itself is threaded?
Sorry, more clarity on my part. Of just a quickie measurement, the shaft seems to be 1-5/8 OD, or something very close to that. It is threaded, for what appears to be a 5/8 threaded screw.

Thanks John!
 
My shop is supplied by a 50 Amp breaker to the sub panel. It has 14 20 Amp quad outlets, my router system (4.8KW), 5HP air compressor, mill (3 HP), lathe (3HP), 300 amp welder, and all the other stuff. Obviously if I fired everything off at the same time the main breaker would trip. But there is only one of me and I can only run one machine at a time, or sometime two. The base load in the shop is about 3 amps, from the battery chargers, idling VFDs, small refrigerator, and other small stuff. All of the lighting combined is about 10 amps, but I normally only turn lights on in the area that I'm working.

What I'm saying here is you don't have to supply power the the shop with the idea of loading up everything to the max. With a 100 amp service you should get along fine unless you are planning on running a full production shop.

Jim, I agree with your general notion. In general, I can only be in one place doing one thing at a time. I tend to think of the other things, more passive, like the fridge, the dehumidifier in the feed and store room, the a/c in my workshop, the computer that will be there(so I can watch all those nifty how-to videos as I try new things) the air compressor kicking on, the barnyard security light at dusk and beyond, horse stall lights, that may be on as we observe a sick horse or an overdue mare, and all the other things that will go on in the barn over which I'll have less than perfect control as to the timing. I guess if you want to think about me and just a small workshop, you're bang-on correct. Problem is that while my workshop will probably represent 80% or more of the average power consumption in the whole structure, there will inevitably be times when that proportion will shift markedly. One of the hindsight shortfalls of this rinky-dinky shack, aka double wide, we purchased when we bought the land etc, is that it is grossly under-provisioned in the electrical department.

Found that out when I started setting up my old school stereo equipment in the living room: Too few circuits shared across too many outlets and found that my stereo, combined with the oven, the drier, and the a/c along with a few lights and other odds and ends could really put us in a hurt. Anyway, that convinced me that excess capacity is good, and lacking any headroom can be quite the bother.

Now in truth, I expect it might cause me a few headaches from time to time if I stick with the 100 amp setup, but most of the time, probably 99%, it wouldn't be a problem. It's just that the 1% always seems to occur at the most unopportune times. Story of my life.

But you're probably right.

Thanks!
Mark
 
Did they hang a pig on the barn pole just for it? If so they may need to resize it for heavier service. I think I would simply get a 200 amp meter socket/base, a fused disconnect (outdoor, the fire dept will thank you for that, seriously), and a load center capable of handling whatever heavy single phase circuits you want to add new, including the entire 3 phase panel. You can then dedicate a larger breaker to the single phase sub panel that is already there and presumably wired into some circuits in the barn. That way not much of the old work will need to be disturbed.

When you run the single phase power to the rotary converter, you then can build a dedicated 3 phase load center that handles only the machinery that runs on 3 phase. Start the converter, and all your machines will be ready to go. And don't ever figure on all of then either starting or running at the same time. Unless you hire a crew and crack a whip. If it's just you and your personal shop, the dollar math can't justify the cost to figure 100% current draw. No one does that even in the commercial world that I know of.

I'm sure some of our resident real electricians will find an error in my methods, and that's fine. That's why we are crowdsourcing this information. It won't hurt my feelings any. I know electric work enough to do it, I feel safely, but perhaps not in total compliance with code in every instance. I don't make nor have I every made my living doing it. Just been around it, and done it quite a bit.
 
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