220V Ez Clutch Motor Woes- Troubleshooting Help?

[MCM Ranch]

It is possible I have some sort of sewing machine curse...

Every sewing machine (of any type) I've ever owned to date has been such an unending source of headaches, that I hand sew - everything.

Then I learned to tool. And saw the lack of attention to detail (and frankly lack of care...) that was going into the tack repairs I was sending out locally... Which left me unwilling to let someone else assemble the chaps, belts, bridles, belt, and other miscellaneous tack items I am building. Hand sewing zippers into chaps is just not on my to do list!

So, I picked up a singer 31-15, cheap, supposedly just serviced and with a sample piece the tech had supposedly sewn...but no power in the shop where it was located. Yes, I learned my lesson... A year of fussing with trying to get it to stop missing stitches (and not be wanton to take off if it actually will pick up all the stitches) as I continue to hand sew.... I had finally had enough and went back to CL

I found a Japanese built industrial leather cylinder arm machine with a 1/2 hp, 220v, three phase motor for a song. Motor date is 1978, very low hours, very smooth action, super clean. It supposedly had been purchased new and wharehoused until last year, when it was purchased and used for one specific project. The only complaint I had was marking from the roller feed foot even on 5-6 oz leather, but I knew that can be taken care of a few different ways and it has other feet. It sewed as slow as non machine sewing me needed, through over 1/2" of veg tan with almost no hesitation on the most thick portions (tho the machine did think I COULD go a little bit faster on the heavier section and it would have been more happy...but a little help with the pulley and it was fine)

Brought it home. Wiring is not a problem, so I pulled a 220 leg, threw in an outlet, replaced the plug end to match the available outlet configuration, plugged it in. Motor came on, but hung (no rotational sound) and then burned a fuse in the switch box (on the machine). Spent days trying to FIND the 2.5x220 slow burn fuses, did, also found a loose screw on a negative connection within the motor as I was waiting to get the fuses (figured it must have gotten jostled in the move?). Ran thru everything logical w my voltmeter, everything looks good all the way through, fired it up... Again with the sound of the motor trying to turn without actually going....

So I am back to disengaging to clutch and turning the wheel by hand...which is at least easier on the hands than saddle stitching the chaps I've had on order for WAY too long!

Is there anything else I might be missing with the motor that worked -perfectly- (and it was so quiet!) less than a week ago? I am so frustrated and just want to get to work in the finite amount of time I can dedicate to this... I'd much rather be up half the night working on my PROJECTS and not my machines

Thank you in advance for your time-

[TomG]

You said it has a 3 phase motor. Silly question, but do youi have 3 phase service to you shop?

Tom

[MCM Ranch]

I would rather risk sounding like an idiot and get this machine running...

It is a pretty standard 220 plug. I wired my exhaust fans in my paint booth, my welder, my dryer, and my range- all of which are 220 and work fine. For the sewing machine, I was a little lazy and pulled a pig tail off my dryer outlet, and installed another 220 outlet in my utility room. The machine then plugs directly into the wall.

[TomG]

The key is still that "3 Phase" you mentioned. You can not run a 3 Phase motor on standard Single Phase 220 voltage that 99.9% of households have. 3 Phase is a commercial voltage and is only avaiable special order

You can buy a convertor to make it work but last time I checked they were $400 - $500.

Tom

[pcox]

3 phase motor should have a 4 prong plug 2, 120 volt 1, 208-220 and 1, neutral. You will need to buy a single phase motor.I would get a servo motor. You need to talk to some of the dealers on this site. sounds like your problems are the machines but the people you are getting them from.

[GerryR]

For $117.00 shipped, you can get a VFD (Variable Frequency Drive) that will convert your 220 VAC 1 ph input to 220 VAC 3 ph output to the motor. It will also give you speed control of the motor, I just put one of these on my Singer 153 W... but have been using them for years, installing them in factories and mills requiring motor speed control and 1ph to 3 ph conversion.

Here's the link: http://www.automatio...0_VAC)/GS1-20P5

If you decide to get one and need some guidance in hooking it up, contact me. I hope this helps.

Gerry

pcox,

The 4 wires have 220 (nominal) between any two of 3 wires, and the 4th wire is ground; no 120 VAC in a 220 VAC, 3 phase system.

Edited July 1, 2013 by GerryR

[Ferg]

I believe you are correct about the voltage readings, IF you read between the two terminals. When you read from ground to the terminals it is a different story.

I have a 40 horse phase converter in our shop. Actually the three phase voltage is 260 Volts with no load in our set-up. I have a 220 Volt single phase sander tied to the two three phase terminals in the fused disconnect that read 120 v each, to ground. The sander is obviously grounded. This connection gives me a 220 v single phase. I can also connect to one of these 120v. terminals plus a ground to run anything requiring 120v. single phase.

The best "fix" for this problem is.....buy a Servo Motor that is 120 volt single phase. Such as one Bob Kovar sells at Toledo Industrial. All of your sewing problems are solved with one simple set-up.

ferg

Edited July 1, 2013 by 50 years leather

[Northmount]

All this discussion below is with respect to AC induction motors.

In a 3 phase electrical circuit, each of the phases is 120 degrees offset from the others. If 220 (normally 208) VAC is the phase to phase to phase voltage, and the circuit is "Y" connected, the centre point of the "Y" (which may or may not be grounded) is 120 VAC from the centre point to any phase terminal. Take the phase to phase voltage and divide by the square root of 3 (which is 1.732) to determine phase to neutral voltage.

Delta connected 3 phase equipment has no neutral; "Y" connected has a neutral centre terminal, though it might not be visible or connected externally.

Wikipedia probably has diagrams showing circuits and electrical wave forms if you want to delve further into 3 phase circuits.

Normal North American 220 VAC household or residential circuits are single phase. The centre tap in the transformer is grounded neutral, so you have 110 to 0 to 110 VAC, or 220 VAC across the outside terminals.

For single and three phase circuits, you should try to balance the loads across the system.

And by the way, if power is lost on 1 phase of a 3 phase circuit, motors may continue to run, low on output power, and overheating. This is called single phasing. Not a good circumstance to be in. 3 phase motors will not start when single phased. But if you spin the shaft, it may continue to run, whichever direction you had spun it. 3 phase motors do not have a starting winding. Single phase motors require a starting winding.

Tom

[CowboyBob]

I made a 220v.3-phase converter out of an old 3-phase motor to run our mill.We had to mount a 110v starting motor on a board & belt it up to the old 3-phase & we turn the 110 on to spin the 3-phase then turn the 220 on & shut the 110 motor off the 220 motor keeps running & will run our mill.

[Northmount]

I made a 220v.3-phase converter out of an old 3-phase motor to run our mill.We had to mount a 110v starting motor on a board & belt it up to the old 3-phase & we turn the 110 on to spin the 3-phase then turn the 220 on & shut the 110 motor off the 220 motor keeps running & will run our mill.

Yup! That is the principle of a rotary converter. Good job.

Tom

[gottaknow]

Just curious, why not just use the correct motors to start with? You lose substantial torque single phasing a 220 motor.

Regards, Eric

[GerryR]

I believe the OP bought a machine with the 3 ph motor on it. It may be less expensive to just replace it with the "correct" motor, but these are just some options if he wants to keep everything "original."

With the VFD, you don't lose any torque, as it generates 3 ph out from the 1 ph in. Also, if the motor can take it, from the rated RPM on down, it can be set to run in constant-torque mode, so you get good torque at low RPM's. If you want to run above the rated RPM's, it will then run in constant-horsepower mode, and the torque drops off accordingly. But it gives a lot of options, not the least of which is variable speed. The phase converters (not the rotary converters, which generate all 3 phases) just start the motor, and then the motor runs single phase at 2/3 the rated power.

[gottaknow]

Heh...so adding a VFD keeps it original? . Forgive me, it's Monday.

Regards, Eric

[GerryR]

You're forgiven, but yes, mechanically speaking.

[eglideride]

GerryR is correct- the VFD is the easiest - cheaper and safer solution....if this were a plumbing project, all you risk is getting wet.

Electricity can kill and or cause fires,,,find a qualified electrician to help you with the VFD. Not worth losing your shop/house- your life or someone elses, over.

[electrathon]

Electricity can kill

Water kills far more people than electricity. Rather than messing with a VFD, why not install a servo motor? About the same price and many people with clutch motors are going that way anyways.

[Northmount]

Most new sewing machine users have trouble with controlling speed on a clutch motor, so yes, a servo, and for their cost is the way to go. A VFD on a clutch motor does give you a range of speed control, but not nearly as convenient as a servo with speed control from the pedal. A VFD on an induction motor losses a lot of torque at low speeds, and tends to increase the running temperature of the motor. It's not a fix all!

If you need low speed torque, get a servo with internal 3:1 gear reduction. You'll be much happier than with a clutch motor on a VFD for similar amount of money, or less. Toledo Industrial has servo with gear reduction.

Tom

[GerryR]

The VFD can operate in "constant torque " mode if the motor is designed for VFD operation (because of both voltage and current (heating) requirements needed to accomplish this). However, you can set the VFD to run with a standard 3 ph motor, and you can set it to run just like a DC "servo" with an external (foot) speed control. I have a 1 hp, 3 ph, 230 VAC, 1725 rpm motor to which I added a 5:1 gear reducer, and then did a further reduction through the pulley, giving about a 7:1 total reduction. I made a foot control (could have bought one, but had what I needed to make one) and can vary the speed from 0 to about 240 strokes per minute (which totally suits my needs). With the reduction, the motor is at ample speed at low strokes per minute to prevent any over-heating and there is ample torque to sew 3/8 leather. If by chance I need to go faster, I can reset the upper frequency limit in the VFD and drive the motor in "constant hp" mode (lose some torque) and move along, for example on thinner, garment material.

My point is that the VFD is as versatile as a DC drive if set up properly. I am not that familiar with the so-called DC servo's sold for sewing machines, but unless there is some sort of feedback from an encoder (which I tend to doubt because of their low cost), it is not a true "servo" but merely a "variable speed" DC drive. So again, the VFD, I believe, is a viable option, especially if you already have the motor, which the OP does have. The DC servos that boast needle position capability, I assume, do have some form of positional feedback encoder or sensors, and would be more inline with a true "servo" system.