Hello Guest it is December 07, 2024, 01:40:26 PM

Author Topic: 1 of the axes is homing, the other 2 don't...cannot find a solution  (Read 3890 times)

0 Members and 1 Guest are viewing this topic.

Hi all


I changed these days the old magnetic switches (unreliable due to temperature changes) with inductive switches. All fine, they seem to work until I try doing the RelAllHome. The X works fine, while Y and A (A slave to Y) do not work in the homing sequence.

In the Diagnostics tab I can see all the 3 switches when they are activated/deactivated.

I tried to make the separate homing from the Diagnostics tab. X again works fine, while when doing it for Y or A, the gantry does not stop when the switch gets activated, but continues until either I stop it or hits the physical limit.

All the switches are identical. Also the settings are similar for the X, Y and A (in Ports and Pins> Input Signals), except that A is slave to Y.
I tried with and without the A-- and Y--  being activated. Same thing. When Y-- is active, I can get the Limit Switch triggered message, and the gantry stops. but in the homing sequence, the switch is activated but Y keeps on moving.
I tried also to unslave A, thinking that it might be smth there. I tried again to home just Y, but again the same result.

When i use the original RefAllHome script, both Y and A approach limits, but when Y hits the limit it continues the same direction, while A moves the opposite direction - but none actually stops as they are supposed to do.

I would be happy to be able to do even just the separate homing, but i cannot get that one work neither. It is very frustrating as I can get very accurate activation of X limit within 0.01mm range, and this performance could improve a lot the quality of the parts I cut.

Any suggestion is more then welcome.

thanks
Marius

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
Re: 1 of the axes is homing, the other 2 don't...cannot find a solution
« Reply #1 on: April 03, 2013, 05:54:13 PM »
Version of Mach? If 066 or 067 try an earlier one and see if the problem is still there.
If its not one of these versions can you attach your xml and I will see if I can find an issue in it.
Hood
Re: 1 of the axes is homing, the other 2 don't...cannot find a solution
« Reply #2 on: April 04, 2013, 06:52:27 AM »
it is 67...at least this is how it shows. This is how I bought from a local company.

attached is the xml file.

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
Re: 1 of the axes is homing, the other 2 don't...cannot find a solution
« Reply #3 on: April 04, 2013, 07:39:24 AM »
Ok I would first try installing an older version, maybe try 057, you will find it here ftp://machsupport.com/Mach/
To install the older version just download it and run it and it will install over the top of your present version. It is always wise to copy and save your licence and xml to another location just in case something goes wrong but it should be fine.
Oh BTW you have the kernel set to 45KHz and you only require about 9 or so , it may be advisable to reduce to the 25KHz.
Hood
« Last Edit: April 04, 2013, 07:42:15 AM by Hood »
Re: 1 of the axes is homing, the other 2 don't...cannot find a solution
« Reply #4 on: April 04, 2013, 05:17:17 PM »
well, some times things can be so much easier if you look into the right place before looking into rocket science or even considering the conspiracy theory :)

it turned out that the maintenance guy just wired the wrong pins - Y to 13 and A to 12, instead of the opposite. But because the switches on Y and A are activated almost in the same time, I could not figure out this.
And only when doing a 2% homing speed in order to avoid gantry bending I could see what happen - A motor started to move ++ without the A switch to activate.... But because Y switch activated, A started to reverse. Same time, A switch never activated so the Y motor kept on moving -- , sending my gantry.

And because the maintenance guy was so confident nothing is wrong with the switches as they were working in Diagnostics tab, it took me more than a full day to get to this conclusion.

Lesson learnt.

Marius

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
Re: 1 of the axes is homing, the other 2 don't...cannot find a solution
« Reply #5 on: April 04, 2013, 05:18:35 PM »
;D

Hood