Artisan Servo Motor Caution Light

[SkookumTack]

Hi, I have an artisan 3200 with a servo motor, went to sew some skirts together today and sewed a test piece first, pulled it out, cut the thread and the machine started going on its own, without me touching the foot pedal, i turned it off then back on and the caution light came on. I've tried unplugging it and waiting but it wont go out and the machine wont work. Is the motor cooked? Its only a couple years old and hasnt seen too much use and zero abuse. Any help would be much appreciated. Just sold my trusty back up Mach 3, now wishing I still had it

[Itch]

I also have an Artisan and sometimes the light will blink,so I unscrew the fuse and then screw it back in..If the machine wants to run on its own check the chain and peddle do you have a little bit of slack ?

[SkookumTack]

yeah there is slack, ive had this happen before too and same thing, i took out the fuse and unplugged the machine for awhile. Ive never had it start sewing on its own before though, maybe i damaged something when i shut it off while it was running all by itself. I have leather drying as i type that needs to be sewn, hope the motor is not cooked.

[gottaknow]

I have about 50 machines with various models of servo motors in the factory. One thing they all have in common, is they really dislike and thread wrapped around the shaft, behind whatever pulley you have. Some have pulleys designed to discourage stray thread from getting caught and wrapped. In the factory, a rouge spool of thread, bobbin, or even thread ripped out and not disposed of properly can get behind the pulley. The tollerances on the sensors are very tight. It actually takes very little to pull the shaft out of alignment of the sensors. This creates a varieties of issues, again depending on your particular motor. When this happens in the factory, I simply remove the pulley, clean the thread out and it's good to go. I also have some servo models that have chronic design issues. Best of luck. We still use plenty of clutch motors, but the servos are nice.

Regards, Eric

[TwinOaks]

Something I had happen with a home machine sounds similar - I was using my old Viking, when there was a tiny puff of smoke and then it started running at full RPM.

Being an electrician, I figured there was some sort of problem with the motor and I started disassembling. What I found was thread dust....aka LINT. Enough had built up that it completed the circuit - that was the puff - and since charred cloth is mostly carbon...which is what motor brushes are made of (plus graphite) it completed the circuit and ran away. Here's the neat part: Motor brushes can wear down (depending on design) and the result is 'dust' with the same properties as the brushes. Add a large enough obstacle (thread lint) and the dust no longer falls out, it builds up and effectively makes another electrical contact.

If that contact isn't cleared, it can cause shorts and overloads.

I cleaned out all the dust, reassembled, and it works fine.

If you have some compressed air, I suggest UNPLUGGING the machine and blowing out the motor housing. It's pure speculation, but you might have had a 'dust contact' build up and the motor is registering it as a direct short (which it is). You may get lucky and be able to blow the contact clear.

[Eldorado]

Hi, I have an artisan 3200 with a servo motor, went to sew some skirts together today and sewed a test piece first, pulled it out, cut the thread and the machine started going on its own, without me touching the foot pedal, i turned it off then back on and the caution light came on. I've tried unplugging it and waiting but it wont go out and the machine wont work. Is the motor cooked? Its only a couple years old and hasnt seen too much use and zero abuse. Any help would be much appreciated. Just sold my trusty back up Mach 3, now wishing I still had it

I have exactly the same problem happen last night. SkookumTack, (or anyone) did you ever get this resolved?

[CowboyBob]

Try leaving it unplugged for a good 1/2 hr & while it's unplugged you might want to take the cover off & look inside as once in a while a wire can slip off & will cause the light to come on.

off & do this too,We have sold machine with this same motor & they seem to holdup very good.

Bob

[Eldorado]

_{Thanks for the thought. We'll see when I get home tonight, should be enough time.}

_{I tried to take the housing off last night and see what was going on (which is on the bottom), but it wouldnt budge. Undid the screws that would appear to be important and couldnt get it off. Looks like the previous owner did the same thing since there are some bent bits where a screw driver was used to pry. Not sure if they got it off successfully.}

_{The other strange thing about this is that from the time I got it delivered (not new) the power button has never turned anything on or off. Its always lit and nothing changes when I push it. its a toggle switch, so it just springs back to where it was after pushing it. The only way to shut the machine down was to unplug it. Its a Servo that is dead quiet, and I assume dormant, unless you are running it, so you can't tell what's going on with it. Not like my Singer 153 with the clutch, where powering up the motor almost dims the lights and it stays growling along until I shut it off.}

_{I knew to unplug it because I'd come down to the workshop in the morning and find it very slowly sewing on its own. I assumed it was the chain slack, but now I wonder if it was related to the issue I mention above.}

[Eldorado]

Thanks Sewmum and SkookumTack,

I got home and plugged it in and the caution light had stopped blinking. But it also started sewing on its own, very slowly. Would only stop when it was unplugged. This suggested to my buddy and me that the issue might be in the throttle lever arm that the foot pedal chain pulls down.

My first test was to remove the rubber stop that keeps the throttle lever arm from going up too high when you let off the gas. When the throttle lever arm could go higher, the sewing stopped and the motor went dormant again. This told me the arm must be out of adjustment.

So I popped the housing on the electronics box (which sits under the motor and into which the lever arm fits). Wasnt easy to get it off, but I got it happen.

Apparently the "throttle" lever arm (when pulled down) slides a simple metal fin in between a thick black U-shaped piece of metal. The closer to the deepest point of the U, the faster the machine runs. I assume the U-shaped piece of metal is a magnet, but I dont really know. It looked like somehow the fin (which is just held in place by the tightness of a screw) had pivoted forward by about 1/8". So when I let off the gas, it was never fully coming out of radius of the U-shaped magnet and so it wasnt shutting off. This makes sense since the machine had to be on a trailer for a couple of hours (probably on some dirt roads) on its way to me a couple of weeks ago.

I tightened the screw and shifted the fin back a bit. I suspect I over-adjusted it because the machine won't run at full speed right now. Probably, the fin doesnt go deep enough into the U-shaped magnet now, but tweaking that is for another day.

I think there is something still wrong with the electronics. Apparently, the power switch had been replaced by the previous owner and either it was the wrong one or is incorrectly installed; or there was something else wrong that he was trying to fix. Right now, the power switch doesnt do anything. Its always on and pushing it doesnt start or stop anything.

Thanks to everyone, we're still working the electronics angle, but I'm able to sew again (even if its slower than before).