partner 0-5 centurion 5(homing problem)

[irtaza]

hello,
I am new to this forum but reading this for a long time,I like the way this forumn is working to help each other.
I bought a milltronics partner 0-5 (1997) knee mill with centurion v control, last month.
when I first started the machine and did the home, the machine ran very fast to the limit switches, in all the axis, and didnot slow down at the end, I closed my eyes, but every thing went well. I ran the machine for about 3 to 4 hours a day for about two weeks and every time when i did the home it goes fast to the limit switches and do not slow down at the end and also at the tool change it do the same. yesterday it went to the tool change position and went out of the z limit. I tried to do the reset and power shut off but didnot work out, so I moved the hard limit markers about a quarter inch lower and then tried to reset again, i was able to reset it and then i did the home sequence and it again crossed the z limit. so again i moved the markers by taking out one of the two screws and the i repeated the same sequence but now it goes to the marker and almost with a jerky movement it comes about a quarter of an inch away from the marker and goes into emergency stop condition. some times it gives the message for y axis too, y axis out of limit, even thiugh it is a bit far away from y axis marker.
please reply with possible solutions.
thanks.
shah

[Dave1]

Shah,
Not real familiar with the 0-5 version but the control should be the same as mine. I have a partner 1 and a partner 6 VMC's. Mine have 3 switches on each axis, 1 home switch and a plus and minus limit switch. It sounds as if your parameters were rewritten to speed up the homing process which may cause the axis's to over shoot the home switches. If the axis overshoots the home switch it may be hitting the hard limits then you'll have to manually turn the screw (with the power off) to get it back on the other side of the limit switches and past the home switch. Be careful that the switch arms don't get bent in the process of doing this. Check the switch arms and make sure they are straight, not bent into a U shape.
Dave

[irtaza]

Thanks Dave1,
i checked the parameters,theseare as follows
velocity toward home, x=60, y=60, z=60
velocity toward mrker, x=3, y=3, z=3.
i even changed the velocity toward home from 60 to 6, but it still goes out of limit or forget its position.

[Dave1]

It sounds as if the switch is not working then. I believe what it should do is hit the home switch, stop, reverse direction and move .1 off it. I think they are very robust switches and you will hear an audible click if it's working. With the machine off, push it down and listen for it, if it doesn't click then it's bad. If it does you could manually move the table to the switch to see if it's pushing it down far enough.
Dave

[jpawelk]

The sequence in which a MIlltronics controlled machine is homed is as follows:

1) The axis moves towards the home switch until the input of the switch is seen by the control.
2) The axis then stops, reverses direction until the switch is no longer seen by the control.
3) The axis then reverses direction again and then the control searches for the marker pulse on the motor's encoder.

irtaza, have you tried reloading your parameters?

[moldcore]

I had to replace a switch once and if I recall there was a screen in the parameters that showed when they made contact so you could tell right off if they were working. It’s been too long ago now to remember where it was. The switches were inexpensive and can be purchased from a number of suppliers for 1/3 the cost of a Milltronics purchased one.

[irtaza]

thanks for all the replies,
I don't know how can I reload the parameters, and from where.
I will also try to find the screen but if anyone knows where and how would I be able to goto the screen to find out if the switches are working, it would be great help.
I am thankyou again for all the replies.

[AMCjeepCJ]

I think you just put the disk in before you power up and it loads automatic but that might have been on the old version of Cent 7 or else it should be under <parms> <load>, otherwise I dunno!

[Dave1]

You need to have the parameter disk to reload them. Your going to have to find the problem first. Moving the switch won't get you anywhere. It could be a corrupt parameter file but usually it won't start when that happens (happened to me a couple times)
PM mholden or jpawelk and see if they have a parameter file.

Dave

[jpawelk]

You can display the switch inputs by pressing F6 Display, then F4 Diag. Pressing F1 through F5 will display the different axis. Display the axis that you are having trouble with. There will be an input (left column) that is labeled home switch. If it is a 0, then the control thinks the switch is not depressed, if it is a 1, then the control thinks the switch is depressed.

Loading the parameters can be done with the parameter disk. Insert the disk into the floppy drive and then press F7 Parm (from the main screen), F7 Load, then F1 Ok. Wait until the control loads the files and then exit to the main menu. Estop the machine if it is not already done, then cycle the power for about 30 seconds.

[br1]

I am new to this forum also and new to a milltronics machine , I have a Partner VM17 version B, I am trying to get up and running, I also have a homing issue, I have followed the last post and I get a "1" on xyz homes, but when I use the home button it goes to home then I get a error 450 Emergency stop Reset Drives, Is this normal? because if I push and hold reset and jog at the same time I can move the machine, If I don't push reset I get the error again. Also I am wondering about a spindle warm up program as this machine has been sitting for several months/years and never turned on, how ever axis's have been changed and appear very smooth.

[jpawelk]

Originally Posted by br1 I am new to this forum also and new to a milltronics machine , I have a Partner VM17 version B, I am trying to get up and running, I also have a homing issue, I have followed the last post and I get a "1" on xyz homes, but when I use the home button it goes to home then I get a error 450 Emergency stop Reset Drives, Is this normal? because if I push and hold reset and jog at the same time I can move the machine, If I don't push reset I get the error again. Also I am wondering about a spindle warm up program as this machine has been sitting for several months/years and never turned on, how ever axis's have been changed and appear very smooth.

That is not normal. The axis are hitting the limit switches. The control shows a 1 for the home switch inputs, that mean that the control thinks the switches are depressed. Your switches most likely need to be looked at. Most likely not set properly.
Spindle warm up program-start the spindle at a low rpm (1500) for about 7-10 minutes, then run it at 4000 rpm for about 7 min, and then max rpm (usually 8k) if the machine is less than 10 years old.