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

[williaty]

A local factory shut down and I got what I thought was a "too good to be true" price on 2 of their machines at their closing auction. Turns out, it was too good to be true. So now I have 2 computerized Jukis controlled by SC-1 control boxes that demand 3-phase power that I'm trying to run at home. I grabbed a single-phase to 3-phase VFD and tried to get one of the machines alive just to see if it had any other complaints but it's immediately throwing the E11 (overvoltage) error on boot up and the main power switch kicks out after about 10 seconds. The label on the end of the SC-1 says it'll run off 200, 220, or 240 3-phase power but it'll throw the E11 overvoltage error even if I reprogram the VFD to such a low output that the phase-to-phase voltage drops to 140V.

 

Anyone have any idea what's going on?

[Matt S]

I'm not an expert on 3-phase, but from what I can figure out VFDs are actually only any good when directly driving a motor. Nothing -- no contactors, no brainbox, probably not even an overload breaker -- should be between the VFD output and the motor coils. The VFD also tends to need to be programmed for the motor size and load, and of course for any inputs (e.g. controls or sensors) that you might want to use to influence the action of the motor. They're not clever/robust enough to make a more general-purpose 3ph supply from 1ph.

Static or rotary converters are more of a generic "1ph in, 3ph out" type converter, but each has its own strengths and weaknesses. Or, I suppose, a motor-generator unit would work, or a fuel 3ph generator. Depending on what you got at what price, and how many bells and whistles you actually want to be functional, you might just be better off flogging the 3ph electronics and buying a couple of good but basic 1ph servo motors.

[kgg]

1 hour ago, williaty said:

So now I have 2 computerized Jukis controlled by SC-1 control boxes

What is the model numbers of the Juki's??? as the manual for those models may help.

kgg

[williaty]

1 hour ago, kgg said:

What is the model numbers of the Juki's??? as the manual for those models may help.

kgg

A DDL-5550N-7 and a DLN-5410N-7. Both running with the SC-1 and CP-130. I found the engineer's manual for the SC-1 and it's how I discovered that the E11 error code is overvoltage, but didn't have any troubleshooting help whatsoever. The machines' manuals don't address the electronics at all.

[kgg]

56 minutes ago, williaty said:

I found the engineer's manual for the SC-1 and it's how I discovered that the E11 error code is overvoltage,

Looking at the manual for the SC-9 and the CP-130 (my search: juki with cp-130 controller wiring and found a good manual called "Control panel CP-130 INSTRUCTION MANUAL - Amazon S3" at s3.amazonaws.com.) and yes it is an overvotage error. What I did notice is there are three wiring diagrams. One for single phase 100-120 VAC, One for single phase 200 - 240 VAC and One for 3-phase 200-240 VAC. With the E11 are you sure it isn't single phase 200 - 240 VAC not 3-phase 200-240 VAC?

kgg

 

[DrmCa]

Are you certain that you are feeding 200-240 voltage? I do not mean to insult your intelligence but you did not mention whether you have a tester or not, and I do not know whether you are relying on the VFD's display.

[Dwight]

Call Toledo sewing machine in Ohio . . . let them give you a price on a single phase motor for those machines.  

Got to be way cheaper than messing with 3 phase converters . . . only takes one phone call to find out . . . Bob will be square with you too.

May God bless,

Dwight

[Uwe]

I’m running my Adler 467 full function machine on a rotary phase converter and it works beautifully. The rotary phase converters are bulky and heavy but they let you run the machine the way it was designed to be used. Since you have two machines requiring 3-phase power, it might be the best way for you to go.

American Rotary Is a good option for rotary phase converters.

[MikeRock]

I sure agree with Uwe if you have several three phase machines.  As a machinist since the seventies, I've watched phase convertors come and go.  The American Rotary is a sound unit.  You can make your own with a three phase motor and a capacitor, but just buying the danged thing is the best bang for your buck if you  are electrically challenged.  I bought a one horse power lathe with a solid state unit on it and hated it from day zero. There were too many solid state circuits and adjustments to make.   For a couple hundred bucks I got a very good single phase motor and went to making chips.  For another set of machines I got a good American Rotary 5 hp unit and from unpacking to making chips was a couple hours. 

For sure, let Bob Kovar set you up if it's just these two machines, you can't go wrong with him. It should be the cheapest route to sewing with your new toys.

God bless

[trash treasure]

What's been said before - A rotary phase converter large enough run both machines, or change over to individual single phase servo motors.  A VFD won't work here.

Just changing over to single phase motors probably makes the most sense economically.