[Gunmachinist]

I have a Bridgeport mill with Anilam 1400M control which I have been working on for the last 3-4 weeks. I have traced all the wiring in the computer cabinet and power panel on the side of the mill which is back to spec according to the schematics given to me by Jerry. Originally my problem was the head would not rotate which was traced to a malfunction in the overload relay. That problem fixed.

I recently disconnected the Y axis servo for cleaning, and when I replaced the cable and activated the servo it took off rapidly like a bat out of hell; if it wasn't for the limit switch I would have had a mill table on the floor. So I disconnected it again after attempting to balance, without any luck. I then disconnected the X axis which was working perfect and connected the Y axis to the X to see if the problem went to the X axis (It did not). Now the X axis took off after I turned it back on, thank God for limit switch, and i cant get either axis back to operating properly. The Y slowly turns as if it needs to be balanced but doesn't react to balance adjustments. Y rotation will speed up or reverse if I jog +/- on the control. X axis will react to balancing but just rotates the opposite way. I did some cleaning with electrical cleaner, and alcohol: still no better. Y doesn't move at all, and X runs like a scalded dog who's tail is on fire...both axis will count +/- so I don't believe it's the encoder, and the servos operated just fine last week. I get no signal on the Y to balance and I can't get X to slow down when trying to balance.

Anyone with Anilam control have experience with this problem? I'm running out of ideas and am starting to dream about large quantities of Tannerite, but I'd really like to have a machine at home so I could make s**t I want.

[Jim Dawson]

The runaway problem sounds like the armature wires were reversed when you put it back together. But if the motor has a plug on it, that's almost impossible. The only other thing I can think of is that the encoders somehow got swapped between X and Y?

[Gunmachinist]

The runaway problem sounds like the armature wires were reversed when you put it back together. But if the motor has a plug on it, that's almost impossible. The only other thing I can think of is that the encoders somehow got swapped between X and Y?

Each servo has its own encoder attached to the servo motor and cant be physically swapped easily, and I don't know how to swap it. Each axis encoder does track(count) when the servo spins. This does give me an Idea that the program perimeters are FUBAR, so I'll check that.

[Jim Dawson]

Is it possible that the cables were swapped at the drive end? As I recall, the X and Y motors turn in opposite directions, so a good chance that mixing up the cables would most likely cause a runaway. Not sure how the parameters would have gotten fowled up.

In any case, I would disconnect the motors mechanically from the ball screws until you get them under control.

[Gunmachinist]

They've been disconnected due to the runaway I had. I need to basically re-tune the servos from scratch as if I just installed a new servo motor, but have no Idea how to start. I can pretty much fix anything mechanical, but when you add electronics to it I'm lost. (electronics make no sense to me)

[Jim Dawson]

A runaway is normally caused by the encoder and the motor running in opposite directions, or a bad encoder. I can't see how just disconnecting the motor and reconnecting it would cause the problem.

[Gunmachinist]

A runaway is normally caused by the encoder and the motor running in opposite directions, or a bad encoder. I can't see how just disconnecting the motor and reconnecting it would cause the problem.

That's what I say, Fin electronics... I hate electronics, more crap to f up..

[Jim Dawson]

The best way I can try to help is to better understand what the sequence of events was.

What was the original purpose of removing the Y motor, just cleaning?

From what I understand you disconnected the Y motor and when you reconnected it it ran away.

Then you connected the Y motor to the X axis drive and it still ran away.

Then you reconnected the X motor back to the X drive and the the X motor ran away.

Is the above correct?

I don't think you need to retune servos unless you have tweaked too many pots on the drives.

[Gunmachinist]

Yes, thats what happened.

[Jim Dawson]

When you move the lead screws or motor shaft by hand, do the encoders count the correct direction.

[Gunmachinist]

When you move the lead screws or motor shaft by hand, do the encoders count the correct direction.

That's whats strange, it doesn't count when the servos are active but after they de-energize due to a lag out fault or I press the e-stop, they will count both ways.

[Jim Dawson]

Well I think that explains the runaway problem. So now the question is why do the encoders quit counting when the servos are energized. Losing 5VDC somewhere when the servos are energized?

[Gunmachinist]

Well I think that explains the runaway problem. So now the question is why do the encoders quit counting when the servos are energized. Losing 5VDC somewhere when the servos are energized?

Yea..:/........ and then 5v is restored when the e-stop is pushed?

[Jim Dawson]

Very strange. Please take a volt meter and measure the 5V feeding the encoder. Let's find out if that is actually happening. I'll try to help you through this, but I need to set up my lathe for the next parts run right now. I'll check back in a while.

[Gunmachinist]

Allrighty, got some information my Multimeter was wrong, needed one that measures millivolts. Got that and...

I found the problem, It was that some dumbass (not me) rearranged the wiring connector on the servo board. :ill: Got them put back according to print and no more runaway... Still gotta do some balancing and adjusting gain, buy I'm in a better place than I was.

[Jim Dawson]

Happy to hear you're making progress. I suspected something like that.

Sounds like you have it under control.