[nordlichtFanuc]

I have an ATC on this VMC that drops a tool every now and then.


Yesterday I saw that the Z-Axis Home Position is slightly to low, so that the double arm is hitting the tool not exactly in the centering groove. Thus I belevieve it can therefore not gripp it correctly.
Now I want to adjust the Zero Return Position of the Z-Axis.

I have read some manuals and instructions and learnt that Paramter 1850 can be used to do a gridshift.

I tried that out, but I cannot change the parameter without getting another error.

The parameter is now set to 1200.
When I try to change positive or negative (to 1000 and 1400), and restart the machine and then try to home, I get the following error:

PS200 Pulse Coder Invalid Zero Return

As soon as I set the value of 1850 back to 1200 and restart again, everything works as before.


Can anyone explain to me why this error is showing up and what I need to do to adjust my Z-Axis Zero Return?


Thanks alot guys for any help.

[Heavy_Metal]

Hi,

Your Z - Zero Return position is G28 G91 Z0.
Most Tool Change macro's use G30 for the Tool Change position.
Make a Tool Change and look if there is a G30 call, maybe use the single block method.
If G30 is used look what parameter stores the Z value or where you can adjust that new position.

Regards,
Heavy_Metal.

[drdos]

Parameter 1241 is the parameter Heavy_Metal is referring to. If you don’t have a value in there then you are not using it. Try 1850 again; make sure that you move the Z axis far enough away from the home switch before trying to reference. If you are too close you will get the PS200 Pulse Coder Invalid Zero Return.

[Heavy_Metal]

Hi,

When you change your Z-Return position (G28) be sure that you measure the "new" Z-level on your product.
The Tool Lenght should be the same but there are different ways to measure them, maybe you have to check them also.
When you have a Tool Presetter and/or a probe don't change the Z-Return position because that can give serious problems.

Regards,
Heavy_Metal.

[nordlichtFanuc]

You guys are great!

The problem really was that I was to near of the zero return switch when I wanted to Home the machine again after changing the 1850 Parameter.

Now it works great! I just needed to get away from the switch und then start homing.

Tool changers works flawlessly up to now!

Thank you very much!

[DEMIAN_CM]

I have just purchased a center for machining, mori seki mv-junior with fanuc 10, but does not bring parameters, can somebody have passed it?, the pc parameters urge me.
My mail is [email protected]

thanks.
Regards

[nordlichtFanuc]

@Heavy_Metal and @drdos

You both seem to understand the homing system very well. Can you please explain me, how the whole system is supposed to work?

I mean:
The Z-Axis has to switches, when homing. First a dog to delecerate and them a contactless switch, which does the homing.

What does the grid shift parameter exactly do? What is this story with the Pulse Coder invalid zero return error? It needs to see the zero return pulse of the coder before the contactless switch, right?
And for setting the correct ATC height, why did I not just change the mechanical position of the contactless homing switch?

I ask, because I still got trouble with that the Z-Axis most of the time, when I power up the machine, and want to home, it triggers a Z Soft Limit Error during homing.
So it seems the machine is thinking Im traveling to far, but the contactless switch has not yet triggered.

Only solution to this is, to starte the machine in IPL mode, disable Soft Limits and then home. After that, everyhting works fine.
But there is something off with my Z-Axis. I try to wrap my head arround on how everything should work..

[drdos]

@Heavy_Metal and @drdos

You both seem to understand the homing system very well. Can you please explain me, how the whole system is supposed to work?

I mean:
The Z-Axis has to switches, when homing. First a dog to delecerate and them a contactless switch, which does the homing.

What does the grid shift parameter exactly do? What is this story with the Pulse Coder invalid zero return error? It needs to see the zero return pulse of the coder before the contactless switch, right?
And for setting the correct ATC height, why did I not just change the mechanical position of the contactless homing switch?

I ask, because I still got trouble with that the Z-Axis most of the time, when I power up the machine, and want to home, it triggers a Z Soft Limit Error during homing.
So it seems the machine is thinking Im traveling to far, but the contactless switch has not yet triggered.

Only solution to this is, to starte the machine in IPL mode, disable Soft Limits and then home. After that, everyhting works fine.
But there is something off with my Z-Axis. I try to wrap my head arround on how everything should work..

Which control type do you have? What is happing is the axis moves during power off and the control doesn't see it. When you try to reference it thinks that you went too far as it didn't see the "move" at power off. Maybe a parameter fix if you have the correct control type.

[nordlichtFanuc]

Hi drdos! Thanks alot for your answer.

Hmm, this would make sense!

I have a Fanuc 10M control.

I just checked, is quity easy to move the Z-Axis down by hand, when the machine is powered off.The machine has a counterweigt, which holds the axis in a quite good balance.

And as you said, it produces the error I see.

Is there a way to disable soft limits, as long as the axis has not yet been homed?
Do you have a specific parameter in mind?

Maybe parameter 5200 to check stroke limit?

[drdos]

I believe so LZR bit

[nordlichtFanuc]

I checked the Fanuc 10 handbook (PDF). I think there is no LZR bit. Probably only newer controls have it?

On the Fanuc 0, the LZR bit seems to be in Parameter 1300. However, the Fanuc 10 does not seem to have Parameter 1300...

[drdos]

I checked the Fanuc 10 handbook (PDF). I think there is no LZR bit. Probably only newer controls have it?

On the Fanuc 0, the LZR bit seems to be in Parameter 1300. However, the Fanuc 10 does not seem to have Parameter 1300...

Check this out. Only 10 has it...

[nordlichtFanuc]

Hi drdos

Cool, I will check it ASAP.

Really funny, as my handbook does not show this bit.. Only to proof I really was not to lazy to look it up, here is it..

I did not know, that Fanuc 10 and Fanuc 10M is different.. hmm..

[nordlichtFanuc]

No luck, unfortunately..

I set the bit a the supposed LZR position anyway, but it did not change the situation.
Maybe I have an old software version?!

Thanks alot anyway for your help!

[drdos]

Could have been added in later versions. You could open up your soft overtravel limit just to get by without dealing with having to bypass each time.

[nordlichtFanuc]

I will try that..

Depending on how much the axis moves when powered off, it will trigger the alarm anyway..

So the real question is, why the axis is moving, when powered off..
Less friction due to wear? Maybe if I increase the weight on the counterweigt a little bit, I will balance out..?

Could this issue maybe be connected with the other small issue on this axis? The humming, as described here?:

https://www.cnczone.com/forums/mori-...s-humming.html