Limited Travel on Y Axis When Auto-squaring < noise on prox switch inputs>

[Mkelcy]

I'm working with a CNCRP (Avid) Pro6060 running DMM2 drives and DMM motors. Y axis is the gantry with master and slave motors. I'm using auto-squaring with the CNCRP proximity sensors.

The auto-squaring works, but only within a very limited range – if I haven’t jogged the gantry to within an inch or so of the sensors, it pretends it hit the sensor on the slave and inch or so off the sensor, and then everything goes to hell as it tries to square the master. The X and Z axes will square from anywhere within their travel.

report_7804732BCC31-0227191699_2019-10-28_17-08-39.zip

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[cnckeith]

photos of machine that shows the switch locations would help in the debug process.

please be specific.. i don't know what " and then everything goes to hell as it tries to square the master." means..

remove the deadband amount.

i see lots of drive fault error messages in the log.. what drives are you using and how are they wired?

[Mkelcy]

As mentioned in the OP, DMM2 drives. It's wired according to the Centroid schematic, using NO limit switches. As for "everything goes to hell as it tries to square the master," when the Acorn tries to "square" the master to the home switch, with the slave "squared" an inch away from its home switch, the gantry isn't happy with an inch or so misalignment the auto-squaring tries to introduce.

As for the faults, yes it's a brand new build for a brand new user. I've been tuning the motors, debugging a false fault condition reported by the (or to) the VFD and otherwise learning the machine. I haven't bother this board with my other issues.

Picture of the machine attached.

[cnckeith]

thanks for the photo.. the gantry home switches need to be at/near the home position of the Gantry not at the opposite end..

please carefully review pages 7,8,9 of the axis pairing guide.
https://www.centroidcnc.com/centroid_di ... _guide.pdf

[Mkelcy]

The proximity sensors are mounted on the gantry and are triggered by a metal "knob" installed on brackets in the home position (the master is visible in the photo - the red bracket). Home position is in the front left corner of the machine in the photo, as marked.

[cnckeith]

ok hard to see, then the switches are riding on the gantry.

Step 1. With the power off, measure how much play the gantry has from side to side. This is the distance one side can
move before dragging the other side along.
Step 2. Mechanically and manually square the gantry. (There are a number of good methods to do this, use a granite surface plate to
sweep and indicator on, make marks/hole in table in corners of large square and measure diagonals etc..
Step 3. Enter MDI and issue M26/X/Y/Z to temporarily home the machine and jog the gantry (with both gantry axis motors
paired) to the extreme end of travel where you want to install the home switches.
Step 4. Install home switches on both sides of the now square gantry...One is called the master, one is called the slave.
Put the master switch on the master side with the master motor put the slave switch on the slave side with the slave motor. Install the switches perfectly in-line with the gantry which is currently now very close to square.
Step 5. Unbolt the master home switch and offset it AWAY from the gantry .025” (this distance can typically be up to two
thirds of the measurement made in step one, bigger machines can usually have bigger distances).
Step 6. In the Wizard set the Master Axis Alignment distance equal to the amount you moved the master switch away
from the Gantry. In our example set the Master Axis Alignment distance equal to .025”
Step 7. Run the Wizard generated home program, check gantry for square. Add or subtract any adjustment amount needed to perfectly square the gantry from the Master Axis Alignment distance. For example.. If i needed to pair the Master
axis .005” closer to the Master Switch to make the Gantry square... .025” - .005” = .020” Set the Master Axis Alignment
distance to .020” Or If i needed to pair the Master axis 005” further away from the Master Switch to make the Gantry
square... .025”+ .005” = .030” Set the Master Axis Alignment distance to .030” etc..

[Mkelcy]

I've done all of that from the Centroid Axis Pairing and Squaring instructions, which I've read multiple times. The machine auto-squares fine if it starts with the gantry an inch or less from the slave trigger. Farther out, it won't travel the distance needed to trigger the slave sensor at the home position, but thinks it's triggered and then racks the gantry as it tries to home the master side with the slave an inch or so away from home. I'll look to see if there's a false slave trigger being reported to the Acorn.

[cnckeith]

watch what is going on while it is homing using the alt i screen..sounds like you have noise causing a false trigger.
what kind of switches are being used?

[Mkelcy]

Pepperl + Fuchs Proximity Sensor (NBB7-F10-E0-V1) on both master and slave: https://www.pepperl-fuchs.com/canada/en ... odid=44230

[cnckeith]

ok have you checked to see if they can be wired in series or not