Need Help!- 300 APC alarm

[mereboy]

Hello everyone,
We have recently acquired a used Hardinge Cobra 42 lathe equipped with a Fanuc 21T controller. This machine powered up with a 300APC alarm for both x and z axis. I found the batteries for the absolute encoders to be dead, which we replaced. Now we still have the 300 APC alarms. I think it wants to have home reset.
Anyone have thoughts on this? The Fanuc 21T is new to us so please be very specific with parameter procedures. Thanks in advance!!!!

[g-codeguy]

You are correct. X and Z home have to be reset. Do you have any manuals for it? Does it have absolute or incremental encoders? For our T42s with absolute encoders X=12.5 Z=14.0

I can tell you the parameter to set, but it won't do you any good if the turret isn't in the home position.

I'm just a programmer, but I've reset home on our absolute encoder lathes many times. If your Cobra has absolute encoders, I can send you (or copy here) the procedure to reset both homes.

I've never had that alarm with lathes having incremental encoders, but assume the method would be the same. Did have the same alarm for the turret on a Takisawa recently when it got a battery change. Simple to fix.

EDIT: Just noticed this was your first post. Welcome to the forum. There are a lot of guys on here much more knowledgeable than I. Especially when it comes to maintenance. Maybe one of them will see this thread, and offer a suggestion or two.

[mereboy]

Thanks g-codeguy,
No manuals to speak of. I believe it has absolute encoders. I am not familiar with "homing the turret", how is that done?

[g-codeguy]

I can't post/send the procedure until I return to work Monday. X-axis has to be set first. The workshift must be set to Z0 before homing Z-axis. The procedure uses a 1.000 inch bar in the collet. You will need a 1.0000 Jo block to set X-axis and a 3.0000 Jo block to set Z-axis. You will see that these size Jo blocks aren't the only ones that can be used once you understand the procedure....it just happens to be the way it is explained by the manual.

Any combination of bar/Jo blocks will work as long as you understand that X-axis must be positioned at X12.5 and Z-axis at Z14.0 before "setting" home. I am going to assume that the home positions on the Cobra will be the same as on our lathes since they are the same size.

EDIT: Check parameter 1815. Look under the APZ column. They should already read zero in the X and Z row. If not, change them to zero.

[g-codeguy]

Well, popped my lower back out this morning getting ready for work. Hopefully icing it today will allow me to walk with less pain tomorrow so I can get to work. I could explain the procedure here if I knew more about your experience with Fanuc controls. (Just how much I'd need to explain.) However, it would have to wait until I can sit more than a few seconds before the pain forces me to move!

[g-codeguy]

You should have 2 PMs. One describing how to reset the X-axis, one on resetting the Z-axis.

EDIT: Don't know if these procedures will work for incremental encoders. Never had to reset home on one, and values in the APZ column read 0 (zero) when machine is working. Kind of think that turret home positions don't have to be reset on an incremental encoder.

[mereboy]

Thanks g-codeguy, I'm currently out of town, but will try this when I return

[tarheels24fan]

I too have a problem with zeroing the x axis,i have a manual,and followed them step by step,the biggest problem i have is that,my axis numbers move on the screen but pysically the turret doesnt,i also have a hardinge t51 that i have rezeroed easily numerous times,seems the manual isnt as clear on the cobra 65,i went to 1850 and changed to zero in x,then proceeded to 1815 apz,also changed that to a zero,asked to power down,now the numbers move but turrent doesnt,any suggestions

[g-codeguy]

I didn't know what might be wrong, but I asked a gentleman who is in today working on one of our lathes. He said to check the Machine Lock switch or button. If you don't have one of those, you probably have a CUSTOM button. Press it and look for Machine Lock. One way or the other your problem should be that the Machine Lock is on.

[tarheels24fan]

machine lock was on! thanks,seems i had too many hands on the fire on this repair

[g-codeguy]

Originally Posted by tarheels24fan machine lock was on! thanks,seems i had too many hands on the fire on this repair

Thanks for letting me know you solved your problem. Too often people never confirm 'yes' or 'no'. Or let us know what the real problem was. Responding with the solution gives some of us a chance to continue our learning.

I've never used Machine Lock or Dry Run in 26-1/2 years of programming/setting up/running lathes. I'm sure there must be benefits for using those options.