Any electricians around? Need help identifying 3ph power (Or lack thereof)

I’m looking at a shop and they say there is 3ph power, but I want to be absolutely sure before I sign a lease. There was someone else looking at the space too, so I need to make a decision one way or the other ASAP. Really hoping I can get my lathe running soon!

I think this is 3ph 240 wired Delta, with no neutral, but I am not 100% confident in my answer. Let me know if you folks have input.

I guess after deciding that is is present, I need to find out the max current as well. The lathe is a used KIA SKT21LMS and it asks for 125A in the electrical diagram! 20hp main spindle, 5hp sub, 5hp live tools, 2hp for each servo. Got it for a song, but feeding it is proving to be a right PITA.

Thanks in advance!

Voltage, amperage and possibly phase should be marked on the main electrical panel. Those images are just junction boxes

Things were poorly marked in general and the guy showing the unit was rushing us a bit- I failed to bring my multimeter or think to go look for the meter for the unit. It seems like this might be a completely separate system from the panel inside the building (But it _is_ pretty much right through the wall outside). Real estate guy said they used to make wine or something in there and had some big machines. I might just have to make the trek out again and look more closely.

The wiring in there does appear to be 3 phase (3 large cables w/ a smaller ground) but I would be looking for the panel to makes sure it has the proper voltage and amperage capacity you need.

Some further info suggests it might be 208v. Reading on here, that might not be a bad thing for my 2003-era japanese lathe? It has transformers in the control cabinet that the previous owner said they needed for some reason, and that might be because it wants 200-220v and they had proper 240. Hmm.

If I don't need them with this setup, it is my understanding that I can also use them to step up the voltage if I bought a modern machine that needed 240 instead of 208.

I might need to drive back out and remember a screwdriver,drywall saw to remove the clearance issue preventing panel removal today, and my DMM. Amperage capacity is definitely a concern, I would like enough breathing room to add at a 4020 sized mill, a bridgeport/manual lathe, then eventually a small CNC mill/lathe to compliment the big ones. Lots of work right now, just not enough machine capacity with my current arrangement and it's time to get serious with things. I figure that's somewhere in the 200A range to get everything on the list. First things first, eh?

I just wish the guy wasn't looking for an instantaneous answer on the unit when there's some complex requirements involved :/

npolanosky said:

I’m looking at a shop and they say there is 3ph power, but I want to be absolutely sure before I sign a lease.

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Save yourself some trouble and call the power company. The records should tell you what is supposed to be at the outside of the building.

The box on the left has two conduits coming out of the ground. Main disconnect?
- The conduit on the right side has wires coded as red/blue/black. Obviously, those connect to the box on the right.
- The conduit on the left side has three wires but I can only see a red wire. Might also be red/blue/black.

Look at the electric meter. The service type should be on the label. If it is three phase, the leg to leg voltages will all be close to the same. If it has one leg grounded, it is not 208 because that would defeat the purpose of the 120/208 service. If there is no neutral, there cannot be the 120 volt lines available.

Bill

Are there power lines from a power pole to the building?, there should be four wires for three phase: 3 phases + Neutral.

After talking to the power co today, I found out 3ph was disconnected in 2006 and they can’t get to the engineering documents easily since they are filed away on paper somewhere. Some extensive reading reveals it is likely 3ph 208V with a high leg, fed off of a 480/277 transformer located elsewhere in the building. If it’s not that, then it’s 3ph 240 wired delta, with no neutral. There *is* a ground present, the wasps built their nest on it. heh.

The power co are going to go dig in the archives and get back to me by the end of the week, and I’m getting in touch with some electricians for estimates on installing a panel and wiring up my lathe/pre-wiring for a mill. In addition, I am going to get some ballpark numbers for another space I am looking at where power is in the building but not in the unit. It seems I have no choice but to make a project of it or to rent somewhere 2-3x as big as I need/can afford.

People keep suggesting an RPC, but a rotary phase converter does not make sense for me due to the size of the machines. I’d need 150+A of regular 240V power just for the lathe, nevermind other equipment in the future. There is an embroidery company in the building running a heck of an embroidering machine (probably 30 heads running at once) off of a small American Rotary rig though- Pretty cool!

npolanosky said:

After talking to the power co today, I found out 3ph was disconnected in 2006 and they can’t get to the engineering documents easily since they are filed away on paper somewhere. Some extensive reading reveals it is likely 3ph 208V with a high leg, fed off of a 480/277 transformer located elsewhere in the building. If it’s not that, then it’s 3ph 240 wired delta, with no neutral. There *is* a ground present, the wasps built their nest on it. heh.

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No. You are mixing up the systems. 208 is the standard line to line voltage for a 3 ph. WYE system, 208V line to line, 120V line to neutral. 3ph. delta is 240V line to line, with no neutral. "High leg" or "wild leg" delta is 240V line to line, with A and C phases 120V to the supplied neutral, and the B phase 208V to neutral, but that 208V single phase is not a standard voltage, and is never used for anything.

A lot of people say bad things about the high leg service, but I've been in business for thirty years running machines up to 20HP with no problems. Biggest inconvenience is if you have a lot of 120V single phase loads, you need bigger than normal panels, as you can only use 2/3 of the breaker positions.

Dennis

Got it, thanks. Tough keeping it all straight! In any case, it sounds like it would play nice with my machine, especially since I got the buck/boost transformers with it.

With all the reading I've been doing, I think I have a better idea of what to look for while shopping around now. Suddenly I'm looking less at the buildings and more towards the sky for transformers and number/config of power lines.

This particular space may not make sense for me if there's a bunch of infrastructure to add, but I've got a couple of new options that popped up today that might be properly equipped.

Just for information sake I just had American Rotary spec me out a RPC for my shop after the local power company asked for $60k to drop a line 50' from a pole out front. They REALLY didn't want to give me 3ph.

That said American Rotary spec'ed an ADX 75. It will feed 204amps and inrush voltage spikes up to 6x FLA. Mine is going to be feeding a SKT25 and Doosan DNM5700. A Phase Perfect would have been nice but at triple the price and a lot shorter warranty for less capacity it just wasn't in the cards.

For reference I have been running my Doosan on a AR 20 for months now. Only thing it won't do is the TSC pump. Also it gets bitchy about large voltage hits while running. But my transformer is an old 10kVa that lets the lights dim when you turn on a microwave so that is not helping.

All my new machines require 220v. The Doosan warranty is void if it varies more than +/- 6%. They checked it when they did the install. I had 240v which would spike to 246v during the day and I had to put on a buck transformer to knock it down 16v to make them happy. Only had to buy the one for $200 since I could put it in line before the RPC. Would have gotten pricey buying multiples for 3ph.

After 14 months of waiting the power company is finally putting in a new 50kVa transformer and going from #4 to #4/0 wire and 400amps in early June. Can't wait to actually be able to run everything at once and not worry about tripping anything. Now I slow roll everything while I wait. It's killing me on 304SS jobs.

IMHO you need to realise your lathes 125 is peak name plate draw, your really unlikely to see that in practice and most the time on a load like that its common to see less than half name plate draw, hence under most electrical regs you get to use a some duty rating fudgery and that can make a big diffrence to costs at these power levels with out effecting performance.

That said, dropping a lot of money on electricals is pretty common in this game on any move. Do you really need such a beast of a lathe? Because its going to cost a lot to get it going and thoes costs take a fair while to make back. If you don't need such a moster, getting something smaller may make a lot more sense,

Noted- You're right, it will probably be rare that I fully utilize it, especially on the power front. I happened to get a really good deal on it, and while I don't necessarily need such a large machine right this second it certainly gives me some options! If I can knock the power requirements back to the largest motor (20hp) only instead of the theoretical max possible load, then we're back in the 60A or less range and it looks like wire sizes are significantly decreased. 1/0 or 1AWG down to 4AWG or smaller with a 50ft run. Much better.

if you were concerned about the peak amps for the PP, don;t be. They take the continuous load and if it is in-spec, the thing should handle motor starts etc. There is no need to over-size it by any more than you might just to provide some future expansion capacity.

npolanosky said:

I’m looking at a shop and they say there is 3ph power, but I want to be absolutely sure before I sign a lease. There was someone else looking at the space too, so I need to make a decision one way or the other ASAP. Really hoping I can get my lathe running soon!

I think this is 3ph 240 wired Delta, with no neutral, but I am not 100% confident in my answer. Let me know if you folks have input.
Thanks in advance!

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What the photos look like to me...

The left splice box was an underground feeder pull box for a underground run in PVC. Doesn't look like service equipment, The bonding is not sufficient for that, and contains no neutral.

Input feeder enters on the left side, Disconnected from the splice and taped off.
Load side goes back underground on the right side to the load, underground original load. Small feeder tap to the right, is still spliced to the load side underground.

Then the right breaker box was added to tap the underground feeder. The breaker was required at the tap point to protect the smaller conductors. Breaker is missing in action. Old load wiring from the tap exited on the right side.

The circuit looks to be made of 2"PVC, #3/0 or #4/0 XHHW, The phasing tape colors indicate a delta hi leg 240V 3Φ, neutral not included, equipment ground wire at at minimum #4-6AWG

Tap to the right looks like 1" EMT, with #3-2 tap conductors, No bonding conductor other than conduit. Terminated in a 100A rain-tite breaker.

Basically a 200A 240V 3Φ 3W underground circuit, tapped in the pull box with a 100A tap.

What it is fed from, and what the second leg of the underground feeds is still in question. There are then two other locations to figure out what is on the other ends of the feeder.

Is the supply end of the feeder and service still in place? meter? transformer? main disconnect?
Does the feeder second leg, feed something inside the space or something outside? another structure?

Could be off base a bit, but that's what it looks like from here. Worth only what you pay for it.

Consider with most leases, any electrical equipment added that attaches to the structure, are to remain when you leave, check the lease.

SAF Ω

I'm about 99% sure that is a 240/120 3 phase 4 wire Delta (aka "high leg") service. In those services, the high leg, which is supposed to be Phase B, is required to be marked with orange phase tape. That's what I see.

Don't get overly concerned with the "high leg". It means absolutely nothing to a 3 phase machine. It's only high (208V) with relation to ground or neutral. Everything is still 240V phase-to-phase. All that means is that when you want to feed 120V loads, you can only tap off of the A and C bus bars with your single pole breakers. It's no big deal at all.

From an equipment standpoint, your electrician must make sure that the 2 pole or 3 pole breakers he uses are not "slash rated", meaning they must not be rated for 120/240, they must be rated as "straight 240V". It just means those breakers will cost about 10% more and you will not likely find them at Home Depot, he'll have to buy them from a wholesaler. Again, not a big deal to you, the user.

Ok, thanks everyone for the input. I have passed on the place- Between distance from home, price, and possible electrical work needed I decided it was not a viable option. Learned a lot in the process though, and I have a couple of really good candidates I'm looking at early next week that are closer to the area I want and are ready to rock and roll, for about the same price or even less.

Assuming one of those works out, my next challenge is finding someone to move my machine for a reasonable price. I have the contact info for the company that did it last time, but they were kind of a PITA to work with and I'd like to get some more quotes this time around.

What keywords am I looking for, assuming I need them to forklift it onto their truck, drive it 30-45mins down the road, and drop it in place at the shop? Rigger? Trucking companies? Machinery Movers? Other?

The last place was a rigging company who was willing to truck it as well, but it seems that's not the case with all riggers. Hell, I have friends with a CDL; Is it cost effective to DIY it? I suspect not, but then I see people on here buying machines and moving them theirselves.

That topic is likely best for it's own thread elsewhere, though.

The term for someone who moves and installs machinery is a "millwright".