Axis Brake Release and Drive Enable

[713cnc]

Hello,
I am running a centroid Acorn6 with a scout board to drive 3 motors, x y and z. The z axis has a brake that releases with 24V. The relay (#11) that controls this brake releases it when cycle start is pressed upon power up.
My motors' enable pin are wired to the En pin for that axis on the scout board. These go high after a reset without having to press the cycle start button This leaves me in a situation where I can move the z axis when I turn on the machine without the e-brake being released.

What is the correct way to deal with this?

Let me note that I would like to keep the e-brake's 24V separate from the acorn's onboard 24V. I have a separate 24V power supply for it and other peripherals (like my limit switches, VFD, and E-stop).

Option 1
Run the axis3 EN output from the scout board both to the motor and to an external relay to release the brake (before cycle start is pressed)

Option 2
Run the axis3brakerelease output from the Centroid relay board to an external relay to controlling the motors' enable pin, so that motors only move after cycle start is pressed.

Option3
Something I have not thought about , or something I am not getting about intended operation.

Thanks in advance for any help offered.

[ShawnM]

Please post a current report from your machine so we can see how you have it configured.

What are you calling the "e-brake", there is no such terminology in Acorn. There's an axis brake or e-stop. The only e-brake is in your car.

I have an Acorn Six (no scout board) and I'm using the "no fault out" upon power up. This output close a contactor that supplies 24V to all my ancillary devices including the z axis brake circuit. When CNC12 opens and the no fault out is enabled and powers up everything. When I start to jog any axis that axis is enabled and can move. Since it's not homed you must be careful not to crash the axis. I have the z axis brake wired to the "axis3brakerelease" and as soon as the drive is enabled the z axis brake is supplied with 24v volts through the Acorn relay output and released. This is normal operation. All before pressing cycle start or homing the machine.

If you have 24v from your second power supply wired to the axis3brakerelease relay output it should work as intended.

[713cnc]

Thank you for you reply Shawn.

Haha, I don't know why I called it an e-brake, must have been from habit! I meant Z Brake.
1) Sorry about lack of report, see attached, as well as the schematics for my machine. I know they are pretty busy, but the brake and outputs are on page 4. You can search for components using the bookmarks in your PDF viewer.

2) It believe I have the same setup as you, but a different perceived result. I am starting to think it has to do with homing. So tonight I started setting up the homing and a million little bugs came up. I will list now, as I think if homing works in the correct order, the e-brake weirdness may work:

-In the Homing setup screen in the wizard, I keep setting Axis 1 M91, Axis 2 M91, and axis3 M92 and exiting and power cycling and it just won't take!
-My cncm.hom file "meat and potatoes" is
M26/Z
M26/Y
M26/Z

I open it back up and it is still stuck on Axis 1 M92, Axis 2 M92, and axis3 M92 and the cnc.hom file is unchanged.

So I manually edited to be what I think it is should be which is
M92/Z
M26/Y
M91/Y
M26/Z
M91/X
M26/X

When I then press reset home on the main page in single block mode, I see it it run M92/Z the error out:
325 limit: Job Cancelled.

Please note that the limit switches are setup according to the the centroid_acornsix_install_manual.pdf, that is to say all limit inputs are green when not tripped and turn red when they are.

Oh, and I don't know if it is related or not, but when I start CNC12, I get 1 reachable IP address and 1 unreachable (see picture).
I also get an error "Invalid command line argument " (see picture)
But I doubt it because when I change the limit travel distance numbers, those are able to be "retained", or written.

Any thoughts?

[centroid467]

From your report, I see you have the switches set as limits only. To use them for homing, set them as FirstAxisHomeLimitOk and so on. With the soft travel limits and homing directions set, it will automatically make the correct setting for the locations of the plus/minus home and limit switches.

I don't think this will do what you want:

So I manually edited to be what I think it is should be which is
M92/Z
M26/Y
M91/Y
M26/Z
M91/X
M26/X

Doing M26 to set the home position before seeking to the switch is going to set the home position where it started. You would probably want this:

M92/Z
M26/Z
M91/Y
M26/Y
M91/X
M26/X

Set "I will create my own home program, do not overwrite cncm.hom" in the Wizard and it should not mess with the home file after that.

[ShawnM]

I just looked at your report and as Centroid467 stated your inputs are not setup correctly for homing. Correct them as noted in his response. I'm not a mill user and I know those machines can home in opposite directions than a router, I'm a router user, so I'll leave that to a mill guy.

As a newbie you should let Acorn create your homing file after you choose the direction you want it to home. Don't try and write one if you are unsure of how to. If you feel you want to edit it after that you can.

On another note, you are using 5.10 with a lot of weird errors on screen and in your error log file. If I were you I'd start with a FRESH install of 5.2 and manually re-enter all your current parameters.

[713cnc]

1) I fat fingered the code you corrected when typing, that was what was entered into the cnc.hom. Sorry about the confusion, and good catch.
2) I look forward to changing the inputs from FirstAxisMinusLimitOK to HomeAll tonight.
3) I will rewire my PNP limit switches in series as shown in the image.
Thanks!

[cnckeith]

command line argument error message

The file C:\cncm\startupOptions.ini has an erroneous empty line with a bunch of tab spaces in the first line. Delete the first line so the file only reads a single line:

here is your file startupOptions.ini from the report. it has an extra line in it.

delete that line and save the file.

[713cnc]

Thabk youso much cncKeith!
Also, changing axisNLimitOK to axisNHome worked.
I believe the brake issue got taken care of, it disables on first jog now.
As a personal update, tool touch off, ATC, limits and probing all working!
Still lots to do (enclosure and coolant, macros for quickly finding center of rectangle) before I am ready to make chips.
Thanks everyone.