[Dustin L]

With the advice of Al (which I agree with) I am using the parameters to reference our turret on our Strippit running a GN-6 controller. The problem is that when ever I get it close the turret deviates way off I'll explain with the following numbers:
The controller has a diagnosis number to tell me how far off the turret is when I first started I set the parameter at 0 and with the locking pins in it showed the turret to be off by -2499 so I added 250 to the param. and rereferenced and then the turret was off by -2186. The following list will show what I changed the parameter to and what the turret was still off,
500 -1969
750 -1777
850 -1615
1000 -1430
1250 -1274
1500 -971
And then when I went to 1750 The turret went way out to -8709 (chair) I shut down and started up without changing and then it came back to 805 so I proceded to 2000 and the turret was -499 so I went to 2250 and then it was back out to -8180 , 2150 -8382, 2000 -8434 So I went back to zero and it read -2461 changed to 2100 and out it went to -8328 back to 1500 and it was off -1013 This morning after being off all night: 1500 -996, 1700 -776,
1900 -583, 2100 -8399 By the way the turret is never been off in the opposite direction it is always the same direction off.
And here I sit :drowning: I'm not exactly sure what to figure I've cleaned the pulse coder "lense/disk" and checked to make sure all brushes were good on motor and tach since an old one we have had run it's tach brushes completely out and a past maintenance guy told the company they needed a whole new servo, but thats another story.
Hope someone can give me some advice any thing would be nice or I guess I will try to mechanically get it to home
Thank You,
Dustin

[Dustin L]

Ok so I set the parameters back to 0 the turret was off -2496 I shut down the machine loosened the drive coupler spun the turret not the motor till the pins locked it into place tightened everything back up making sure my scribes on the motor shaft had not changed and when I fired it back up without changing anything I referenced the machine and the turret was off by -8103 Is this possible, The guy at lvd said it seems like the pulse coder is skipping a nole (I think he called it a nole) would that mean the pulse coder is junk.
Thanks Dustin

[Al_The_Man]

Are you sure there is nothing mechanical like a shear pin, it almost sounds like it?
Al.

[Dustin L]

No I checked the whole drive system it makes use of the locking collars the ones that slide into each other that to get apart you use jack bolts to "split" them apart. I scribed all the connection areas and what each one individualy as the operator was running the turret. There is a home switch it is a magnetic disruptive style switch which has a steel flag pass through it the flag however almost completely exits the switch when it stops where it wants to, but when I pull the turret to get the pins locked in place there is a sufficient amount of the flag still in the switch the flag looks to be about 12" inches or better and it is just the trailing end that stays in between the switch. I'm trying to get ahold of lvd to see how it should be set and how it actualy triggers the controller whether it be on then as soon as it goes off it starts to read the pulse coder or what.
Dustin

[Dustin L]

I got it Al I redid everything setup the home switch with as tight as tolerance as possible and when I referenced it at 0 parameter it was only off by -207 so I added to 200 to the parameter and now she homes in at -20 to +20 everytime. I did have one more question for you though I don't think I fully understand the difference between a pulse coder and a resolver is there a difference do both require a seperate home positioning switch on the axis? I was lead to believe that when a resolver is in use there is no home switch. Is this true?
Thanks for the help again Al
Dustin
P.S. I don't know how this site works, but I believe a guy like you who has always been a huge help ought to get some sort of incentive for all you do!

[Al_The_Man]

P.S. I don't know how this site works, but I believe a guy like you who has always been a huge help ought to get some sort of incentive for all you do!

Thanks! I will bring it up at the next meeting.

An encoder can be 5v quadrature square wave or in the case on Heidenhain type, can also be 11ua quadrature sine wave.
But on both cases there is often, as you say, a 1/turn reference pulse.
With a resolver, there is only two quadrature sine waves out, so a reference has to be obtained in a different fashion.
Al.

[gridley51]

That procedure seems very similar to the one for setting the turret on a W&S WSC12 lathe with a 6TB control that I have.I can remember having to do something similar when I bought it.