excessive servo lag in an axes

hi every body
please help me about this problem.
we have following errors frequently on our Bridgeport 1000 CNC machine which is equipped with HEIDENHAIN 426PB controller:
1- excessive servo lag in X
and then
2- movement monitoring error in X
after these Consecutive errors, we have to reset the TNC to work with it.
we change the X encoder cable, lubricating pipes , change the oil viscosity but it has not work.
can you help us about this errors?
it should be noted that we also have changed the lubrication parameter of machine (MP4060) FROM 0 to 5 mm, but it seems our oil consumption has not changed and it is low still. (about 1 litre oil per 350 hours work. is this enough to lubricate the guides and etc.???)

...AC Siemens Amp's? ...what model numbers ? any error codes on the Amp's?

Quote:

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Originally Posted by vahidkarimi84

hi every body
please help me about this problem.
we have following errors frequently on our Bridgeport 1000 CNC machine which is equipped with HEIDENHAIN 426PB controller:
1- excessive servo lag in X
and then
2- movement monitoring error in X
after these Consecutive errors, we have to reset the TNC to work with it.
we change the X encoder cable, lubricating pipes , change the oil viscosity but it has not work.
can you help us about this errors?
it should be noted that we also have changed the lubrication parameter of machine (MP4060) FROM 0 to 5 mm, but it seems our oil consumption has not changed and it is low still. (about 1 litre oil per 350 hours work. is this enough to lubricate the guides and etc.???)

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Servo Lag is normally caused by a high load, on the Axis this could be Ballscrew, thrust Bearings, or slide ways / Rails are bad or worn.

That should be enough oil if it is getting to where it needs too, if something is failing like a Bearing then no amount of oil is going to change anything. you will have to check the Axis Ballscrew Plus Bearings.

Is your machine on linear rails or solid ways??

Dear Mactec54 ,thank you for your answer. we checked the lubrication situation in X Ballscrew it seems it had no problem i.e. I could feel the oil layer on Ballscrew. also on slide ways.
I think our machine is on ways. I dont know what "linear rail" is.
also let me consult with you about the subject " high load" you mentioned. for decreasing the load, we decrease the acceleration of all axis from 4 to 2.5 with MP1060. can it be usefull ?
also we check the encoder cable of X motor, and seal it tighter with layers of plastic tube varnish to prevent probable short circuit between pins due to moisture and water. can it be usefull ?

all the best

Dear Machinehop5
if you mean what drive model , yes it is Siemens. I take some picture of machine cabinet as in the attachment for your kind attention.
meanwhile I attach some picture from the report of TNC itself.(descreption of 2 serial errors by TNC itself) . as you can see in pictures, TNC recommends to decrease the Uz. I do know what Uz is and how I can change it?

the best

You should also check for loose bearings and backlash.

Cheers
Roger

Quote:

---

Originally Posted by vahidkarimi84

Dear Machinehop5
if you mean what drive model , yes it is Siemens. I take some picture of machine cabinet as in the attachment for your kind attention.
meanwhile I attach some picture from the report of TNC itself.(descreption of 2 serial errors by TNC itself) . as you can see in pictures, TNC recommends to decrease the Uz. I do know what Uz is and how I can change it?

the best

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Those faults are giving you some things to check like Power supplies.

It could also be the servo motor itself that is causing the problem, if everything else checks out.

Hi,

Does the X-axis move at all? If not, I believe the Siemens LT-modul on X-axis is broken.
You can test this by exchanging the LT-unit with Y-axis and test it again.
Put the machine in Emergency Stop, go to " Programming and editing" mode, MOD-button and give the code 95148 to get to parameters.
Change the parameters 120.0 and 120.1 values (put the value in 120.0 to 120.1 and 120.1 to 120.0). Exit the parameters with END.
Power of the machine, change the motor cables on the LT-units, X to Y and Y to X.
Put the power on, switch on the power. Now, if the X-axis works and you will get the error on the Y-axis the LT-unit is broken.
This happens very often with the older LT-units.