Need Help!- PS200 PUlSE CODER INVALID ZERO RETURN

[vladimir1409]

hi guys need some help

I have a Victor V center with a fanuc 10M,
few days ago it started showing alarm on the X-axis when I try to do a home position(zero return).
the machine was working just fine it didn't have a crash,heavy cut or nothing similar, the alarm started showing one morning when I powered up the machine...

I read in some of the threads something about grid shifting-parameter 1850, the value for the X-axis is: -1080 I change it to -540 but no result the alarm still goes on approximately 2.7mm before the home position (could someone clarify to me in short what does the "grid shifting" do???)

I also tried with moving the table as far as I can from the home position an then ref. position, it rapids to the dog and decelerates as it should but alarms out when it reaches the end of the dog, no luck again ...

does this mean that the encoder is not working (no marker signal) or it could be something else... ????

Stevo, I hope you read this thread, in one of threads I read that you bought a new encoder for the 4-axis and still you get the alarm if you don't move the axis far enough, did you solve this or the alarm pops up again if don't move far enough?

any suggestions?/??

thank you all in advance

[Al_The_Man]

As you suggest, it appears you are not seeing the marker pulse?
Do you have AC or DC servo's?
Al.

[vladimir1409]

DC servo's, yellow cap motors.

[Al_The_Man]

Did you try tripping the home switch before the axis reaches the dog and see if it will register home in another position?
Al.

[vladimir1409]

this is strange?!?

I harassed the machine a little bid(for more than an hour), I was sending the machine over and over again in ref. position and it suddenly went i home position (X-axis)...

I will try again tomorrow morning and see what happens is it going to work or do I have to harass the axis again in order to do a home position

any suggestions what else could trigger this alarm???

[Al_The_Man]

Could be a cable connection or break due to flexing?
Al.

[vladimir1409]

hey Al thank you for your replies,

this is what happened this morning I powered up the machine, try to send the X-axis i home position alarm pops up again.

I powered up again the machine and this time I just left it like that form more than 2 hours and then tried to do a home position of the X-axis, it referenced without any problem, it's like the machine needs a time period to be powered on and then it will work, I may sound silly but that's the way it is...
any ideas???

I dont think its the cable because the flexing and position dot have any influence on the alarm( i tried flexing it and in different positions)

[Jerry Shorter]

One problem that I had with the Victor V-Centers was metal chips packing around the home/limit switches. Also, the wire leading to the switches will, over time become very brittle and sometimes break causing an intermittent connection. The switches are under the table on the right side of the machine for the X-axis. I ended up leaving the cover off so that I could periodically blow out the chip accumulation.

Sorry, the switches under the table on the right side of the machine are for the Y-axis, the X-axis switches are under the covers on the front of the machine. still that area will also get packed with chips.

Jerry

[Gstock]

Originally Posted by vladimir1409 hi guys need some help I have a Victor V center with a fanuc 10M, few days ago it started showing alarm on the X-axis when I try to do a home position(zero return). the machine was working just fine it didn't have a crash,heavy cut or nothing similar, the alarm started showing one morning when I powered up the machine... I read in some of the threads something about grid shifting-parameter 1850, the value for the X-axis is: -1080 I change it to -540 but no result the alarm still goes on approximately 2.7mm before the home position (could someone clarify to me in short what does the "grid shifting" do???) I also tried with moving the table as far as I can from the home position an then ref. position, it rapids to the dog and decelerates as it should but alarms out when it reaches the end of the dog, no luck again ... does this mean that the encoder is not working (no marker signal) or it could be something else... ???? Stevo, I hope you read this thread, in one of threads I read that you bought a new encoder for the 4-axis and still you get the alarm if you don't move the axis far enough, did you solve this or the alarm pops up again if don't move far enough? any suggestions?/?? thank you all in advance

Some Fanuc Controllers require you to hold down the "can" button & the "P" button while powering up if the axis was accidently moved while power was off.

Also, grid shift changes the axis one mm for each 1000 entered in parameter.
You are working on a pulse that starts counting when axis exits the dog or
sensor and stops when the count is reached. Grid Shift can be positive or negative. I usually start with "0" and go in the direction needed to move to
home position. Example: If you needed to move axis 2.7 mm to reach home
you would add 2700 to what you had in parameter. Hope this helps.

[stevo1]

Vladimir,
I still have the same problem on my rotary axis of getting pulsecoder alarm if I do not back it off far enough from the switch. With the headaches that I have gone thru on that machine....having to take and extra 30sec at powerup in the morning to reference the machine is well worth the weight aspirin.

I would do as already suggested about checking the wires/connections and then as Al stated trip the switch manually when trying to reference. It sounds like your encoder is working but you could also be getting noise thru it as well that could be throwing it off. I would however suspect that the marker is to close to the decel switch. You can physically move the switch or adjust your gridshift parameter.

Stevo

[Thinker2007]

Dear Vladimir, in other cnc type I had 2 times similar problem and the cause were different but related; 1: encoder malfunction, and 2: lost of software limits values.
the encoder malfunction because the connector had ambiental wet; the lost software values caused by an storm lightning.
I hope that these comments helps you.

[stevo1]

What alarm are you getting in the X. Number and message.

Stevo