[DanielWC]

I cant get my Soft Limit and DROs to turn green when Ref AllHome. I entered my coordinates in Home/Limit Configuration. Using the Go to Zero each axis returns back.. When hitting RefAll Home the Z axis rams into the limit switch and the emergency stop has to be used to stop it

[joeavaerage]

Hi,
SoftLimits are absolutely useless UNTIL the machine is homed.

When you engage SoftLimits you are instructing the machine that the X++ limit is 545mm away, and the X-- limit is -100mm away...etc, but that assumes the machine knows where it is to start with.
Once you home to a defined and accurately repeatable location EVERYTIME then and only then do SoftLitmts make sense.

When Mach is Homing it ignores Limit switches.

This dates back to the earliest days of Mach when people used limit switches as double duty, ie a limit AND a home, and that in turn was caused by the fact that there were so few inputs you had to combine
functionality in order to use a few inputs as possible to match the parallel port. Thus when you hit <RefAll> Mach ignores the limit switches and is looking for a home switch event. If you have misprogrammed Mach
such that it never 'sees' a home switch event it will keep on going until it does ......CRASH!

I use Mach4 and have done for ten years, but in respect of homing it is very similar to Mach3. I have nine limit and home switches. I have a limit switch at each end of the X, Y and Z axes (X++,X--,Y++,Y--,Z++,Z--)
accounting for six switches, and then I have three home switches, one on each axis set to trigger 2mm 'inside' the limit. I use an Ethernet SmoothStepper which has plenty of inputs so each switch has its
own dedicated input....the Mach need never be confused about whether a signal is a limit event or a home event.

Craig

[elephantcnc]

It sounds like there might be a configuration issue with your home/limit switches or the way the machine's reference position is set. Here are a few things to check and troubleshoot:

Check Home/Limit Switch Settings:

Double-check that your home switches are set up properly in your configuration.
In Mach3, make sure you have the correct pins assigned for each axis’s home and limit switches in the Ports and Pins settings. Also, verify the active low/high setting.
Check Machine Coordinates:

Ensure that the machine’s home position is correctly set in the Home/Limit configuration. The machine should know where the limit switches are relative to your machine’s origin (usually where X, Y, and Z = 0).
When you press Ref All Home, the machine should move to the home position, but it should not collide with the limit switches if the machine coordinates and limits are set correctly.
Check Travel Limits and Soft Limits:

Make sure that your Soft Limits are configured correctly. If the soft limits are too restrictive or incorrectly set, they can prevent the machine from moving freely when it tries to home.
You might need to adjust the soft limit boundaries in the Config ? Soft Limits menu to ensure they are within the actual physical range of your machine.
Refining the Z Axis Homing Process:

For the Z axis, ensure that your Z homing position is properly configured, especially since it's ramming into the limit switch. It could be a sign that the Z axis home position is too far up or that the direction for homing is wrong.
If your Z limit switch is normally closed (NC), check that you have the correct setting for it in the Input Signals and Ports and Pins settings.
Check Motor Direction:

If the Z axis is moving in the wrong direction, you might need to invert the motor direction in the Motor Tuning settings.
Test with a Smaller Move:

Try jogging the Z axis manually (without the reference home) to make sure it’s moving in the right direction and is not overstretching any limits.
Debugging Process:

If the machine is continually ramming into the limit switch, manually move the Z axis to a safe position and check the wiring of the limit switch. Try homing the Z axis on its own (click on Ref Z) to see if the issue persists. This can help isolate whether the problem is specific to the Z axis or a more general configuration issue.

[Dadsmill]

Hello, can you please help me with the same issue. I had them all green. the next day thew are red and I can't change it. I'm trying to home to the front left. The homing and limits. I guess I'm not getting right. I have a large size table. Roughly 4ft6 x 2ft5. And I'm running in inches

[joeavaerage]

Hi,
the best way to home is with Home switches. When you press <RefAll> the machine would drive at some subdued pace towards the home switches and on reaching them would zero (or apply a programmable offset)
machine coordinates. Success is indicated by the axis LEDs going green.

In absence of Home switches you'll have to manually jog to some repeatable location, in your case you have chosen the front left, and then press <RefAll>, but with 'Home in Place' checked for each axis in the Homing and Limits tab.
'Home in Place', means as it says, that when you home an axis for which Home in Place is active it will reset to zero (or apply a programmable offset) the machine coordinate for that axis right where it is. Success would be indicated by
the axis LED going green.

As I've told you before without Home switches you will always have problems while limit switches are less important, but having reliable and repeatable home switches is in my opinion essential. Before you ask you'll need to be 100% familiar
with the motion board and its plugin in order to implement home switches, a 'blue Mach3 board' is not 100% familiar. Have you even opened and had a look at the motion board plugin in Mach3? All I can tell you for sure is that there is no support
for the plugin, and unless you can find some documentation from one or more users from the Mach3 forum then there is no documentation either.

Craig