Cobra Eps, Please Help If You Have One

[talon]

I recently purchased two sewing machines from Steve and he has been great to work with and the machines are very nice. I am having a problem with my EPS system, which is very likely user error.

First I would like to say that Steve has been very helpful and provided great customer service, I'm only seeking more information here so I know what I should be looking for so I can talk intelligently with Steve.

Let me tell you the issue I've had, nearly identical issues on two machines with EPS. (this is spcifically on the Class 18, but I have had similar issues on the class 4)

The needle never stops in the down position, and the servo is constantly giving and E8 error code (and I've seen and E9 error code a few times). It will stop in the up position occasionally and will show Pu on the servo (I think this means Position Up). The red light on the synchronizer (mounted to the hand wheel with the marks lined up as instructed in a set up guide I received) illuminates at this point (and every time the needle is in the up position).

Pressing the heel down, when you've manually put the needle in the lowest position, will sometimes cause the needle to raise, but it is inconsistent.

While trying to understand how the system works I noticed that the red light only comes on once per revolution of the hand wheel, I think that each time the red light comes on it send a signal to the motor to stop its rotation. I pulled the cover off of the synchronizer and noticed that there was one magnet, put a hole for a second one (this appeared to be the sensing mechanism). It seems like there should be a method for sensing the high point and the low point of the needle, but the synch. is unable to provide that info.

Any thoughts? Does your synchronizer have two magnets? does the light come on at the high and low point of the needle?

Thanks!

[mikesmith648]

I am buying one in October........Cobra4 with EPS.........I would just call Steve!!

[DDahl]

I have two EPS driven machines. The error you mention is generally caused by the machine turning too slowly. This is because the servo uses a time delay test to protect your fingers and the machine from an open loop situation (position sensor not working properly). If it takes too long to get to the stop point the servo gives up turns off EPS and flags and error.

A quick test to see if this is the problem is to set the max speed of your machine to 10 or above. If the problem goes away you have found the issue. Then just slow the max speed down to where the servo stops positioning properly and speed it up a notch.

You can also inflict this problem on yourself if you change the belt reduction ratio to slow the machine further. If this results in the position sensor taking too long to hit the target, the servo will throw in the towel and flag the error. Ask me how I know.

Dave