Can anyone help me with a running a 3-phase Juki at home?

[oldfarmboy]

On 1/20/2022 at 7:41 PM, williaty said:

I am fairly sure this is a place where the differences between how the US delivers electricity and how the EU does it probably makes a difference. In pretty much all single-family residences, we get something that gets called single phase even though that's a damned lie.

No it's not a lie. It is still single phase. This guy has it right.

On 1/29/2022 at 11:35 AM, 480volt said:

Since I’m in the business, I notice when people start using electrical terminology incorrectly. What you get in US homes is single phase power, with the transformer winding between the two legs center-tapped to provide the neutral. As far as I know, actual two-phase power, which requires four wires, is used only in downtown Philadelphia, which has legacy buildings permanently wired that way. It’s supplied via Scott-T wired transformers, since no utility generates anything but three-phase. Look it up if you like, but you and I will never see one.
Three and four-wire description means something very specific in the electrical industry: three-wire indicates a panel or equipment operating on three-phase with no neutral, therefore a single voltage, typically 208 or 480. Four-wire indicates the presence of a neutral, therefor two voltages: typically, 120-208 or 277-480. The ground is never considered as part of the set of conductors.

But none of this has any bearing on the OPs question.

Anyway, if the motor is not integral to the accessories, probably easier and cheaper to just buy a single phase motor for it. Otherwise I’d try an RPC. Then you can power a mill, a lathe, big drill press…

 

On 1/20/2022 at 7:41 PM, williaty said:

 

So I need to turn the 240V service I have (which is 2 120V phases 180* apart) into 3 phases separated by 120* and producing a phase-to-phase voltage of between 200V and 240V to make this control box happy.

 

[enin5479]

I think I am in the middle of making the same error.  I am looking to purchase this machine at an excellent price, but when I asked if I could test it out, they said it was missing the plug.  I noticed it was a 4 wire plug and since then I have been trying to figure out if my garage can handle it. Or if I would need to run a whole new 220 circuit or something to power.  I am not even sure what type of plug to put on it or what type of outlet to get.  

Any insights would be appreciated.

[Uwe]

There should be a sticker on the motor or controller box that specifies what the power requirements are. It’s very likely that it’s a 240V 3-phase setup. You’ll need a 240V outlet in your garage in order to use a rotary 3-phase converter. There is no viable path that takes you from a standard 120V outlet to 240V 3-Phase power. 

The 3-phase plugs and receptacles I use for sewing machines are NEMA L15-20 which look like this. This is the receptacle on the 3-Phase converter and the plug on the sewing machine.

 

For the single phase 240V receptacles on the wall I use NEMA 6-20P plugs and NEMA6-20R receptacles. This is the 240V outlet in the wall and the plug on the 3-phase converter.

 

Edited February 7, 2023 by Uwe

[Wizcrafts]

1 hour ago, enin5479 said:

I think I am in the middle of making the same error.  I am looking to purchase this machine at an excellent price, but when I asked if I could test it out, they said it was missing the plug.  I noticed it was a 4 wire plug and since then I have been trying to figure out if my garage can handle it. Or if I would need to run a whole new 220 circuit or something to power.  I am not even sure what type of plug to put on it or what type of outlet to get.  

Any insights would be appreciated.

At this point I would recommend that you remove the motor, control box and all wires. Then buy a modern 110 volt servo motor and switch box, plus a new led work light that plugs into the back socket on the motor.

[DonInReno]

I’d also vote for not spending any money on trying to get the 3-phase motor controller to work, and just swap in a 110v motor.  

That’s not to say it’s not a good machine - I have a ddl-555 with a simple replacement servo motor that works great for light weight fabric sewing, but they are old enough to not be worth more than $250 with a working 110v servo.  

[rlevine]

I'd suggest getting the engineer manual for the control system. That's an SC-120 control panel, pdf is here: https://www.supsew.com/download/Juki/Juki SC-20, -120, -220, -320 Engineer’s Manual.pdf

Look on the left side, rear corner of the control box for the power rating, don't go by the number of wires in the power cord. The motor plates all state the DC voltages supplied by the controller, and all the machines have 250v fuses.

For me, the reason to keep the original controller has been the automatic trimmer. Mine is a DLN-5410-6 heavy, and for bag work, it's a joy.

Attached are a snap of my rating plate, and the illustration from the manual showing the variants.

 

Edited February 7, 2023 by rlevine

[williaty]

4 hours ago, enin5479 said:

I think I am in the middle of making the same error.  I am looking to purchase this machine at an excellent price, but when I asked if I could test it out, they said it was missing the plug.  I noticed it was a 4 wire plug and since then I have been trying to figure out if my garage can handle it. Or if I would need to run a whole new 220 circuit or something to power.  I am not even sure what type of plug to put on it or what type of outlet to get.  

Any insights would be appreciated.

 

Like I told you on Reddit, after consulting with the guys here, with multiple sales shops and repair shops across the US, with the US distributor/importer for Juki... it's just not worth it. If your brain box is meant to run on 3-phase power, the only likely to succeed way to get it to run on domestic power is with a rotary phase converter. Those cost a lot more than you paid for the machine. Same with trying to switch the electronics on it to their single-phase counterparts. Costs more than a brand new machine.

 

If there were an economically viable alternative, I would have done it.

 

In the end, I ripped all the fancy off the DDL-5550 and the DLN-5410. On the DLN, I put on a basic servo with positioner. I ended up selling the DDL-5550 because I found a DDL-8700N-7 0WB single-phase version on Craigslist for just $400. I sold the 5550 for $250, so I had very little incremental cost to move up to something easy.

 

Keep hunting, don't settle.

[enin5479]

Thank you everyone for all of the valuable information! I really appreciate it.

[Quade]

I run my 3 phase lathe and drill press off a $200 VFD

https://www.amazon.com/HKS-Variable-Frequency-Controller-Converter/dp/B09Q8JVTVN/

Here's a cheap one. 110v single phase to 220 3 phase. 

Instead of that, I'd install a 750 watt servo motor and simply not use the servo the machine came with. 

https://www.amazon.com/Consew-CSM3000-Sewing-Machine-Electric/dp/B01N1L1P7G/

It's a relatively simple install. 

[bladegrinder]

I bought a used 3 phase surface grinder a couple years ago and while looking at the controls and wiring I discovered the oil pump was 110 single phase then found a transformer inside wired with a few other things. I connected a VFD to the motor but ran a dedicated 110 single phase line to the oil pump.

VFDs don't put out a clean 3 phase like you would get from your utility, as mentioned by 480volt the motors connected should be inverter rated. mines not, so researching what that meant I learned a non inverter rated motor on a VFD can actually get bearing damage over a very long time of operation, something about the way the VFD feeds it.

throw in a computer board and your asking that machine to throw an error code. you may be able to isolate the motor to the VFD but from what I found is you can't have any controls or switches between the VFD and the motor, which would eliminate any use of other electronics on your machine. they simply cannot have any sort of function on the motor after the VFD.

I could me mistaken about this but I knew what I was getting into with this surface grinder, just stumped a while about the oil pump. I wish you luck with your machine, if nothing else, you'll still have a great machine but without all the bells and whistles.