Z-Axis don't work - gshield don't light the led

[LarryM]

@ClausArnold
If you have homing enabled and soft limits enabled, the machine powers up in an alarm state. Normally you would use the homing sequence to home the machine and clear the alarm. At that point with soft limits enabled the machine will not use the switches anymore.

This has advantages and disadvatages.

For your testing without being able to home the machine, also turn on hard limits ($21=1). This will cause the machine to monitor the swtiches again. This will help protect your switches and it will cause an alarm if you press a switch.

One thing you should watch for is electrical noise which can cause false triggers on the switches.

All of this is to help you test a little while you wait for your new gShield. In normal operation, I recommend homing and useing soft limits with hard limits turned off.

Also see:

Homing/Limit Switches

Looking at things from the grbl perspective, the term “limit switch” only applies for the X-carve if you use hard limits ($21=1) . Looking at things from the grbl perspective, all other cases for the X-carve the switches are “homing switches”. Homing switches allow soft limits ($20=1) to work. For this case the “limits” depend on having done the homing cycle and on the low end the limits are 0,0,0 and the limits on the high end are set by $130, $131, and $132. After the homing sequence the swi…