ClearPath Hard-Stop Homing

[legacymachine]

Is it possible to use the hard-stop homing feature of the ClearPath SDSK motors with the Masso control.

The problem I am running into is with how the HLFB works on the ClearPath... it causes the Masso control to believe that it is always up against the stop because HLFB is high when the motor is sitting (it goes low during a move and the hard-stop would cause it to go high again to trigger the home, but it never gets to this point because as soon as you command the homing sequence, it sees high and just performs the pullback move).

Is there any work-around for this?

 

[masso-support]

As the clearpath motors dont have a seperate signal for alarm and homing, the HLFB can't be used to give feedback to MASSO about homing.

We have people using clearpath hard stop homing with MASSO and is done in the following steps:

1. In the clearpath software set the motor to home when enabled.
   
2. Wire the enable signal of the motor to estop.
   
3. In MASSO homing settings in the homing sequence untick all axis sequence where the clearpath motors are used on.
   

Homing steps:

1. Once the machine is powered up, when the enable signal is give through the estop button, the clearpath motors will start homing.
   
2. After all the axis have homed, press CTRL+ALT+HOME for MASSO to register that you have homed the motors.
   

IMPORTANT: With the above setup all axis will home together and can cause issues especially in mills where generally the Z axis is homed (moved up) first to move away from workpiece and then X and Y but using this method will move all axis together. Its preferred to not use the clearpath hard stop homing option as the motors dont provide proper homing signals for CNC controllers.

 

[legacymachine]

Thanks for the info... I'll give it a try.

Seemingly all that would need to be done to make it work is to add an option (or check box) on the Masso homing setup to ignore the input value at the beginning of the homing sequence (then look for it again as soon as homing begins). This would allow the ClearPath motors to start moving (thus HLFB would go low) and then the HLFB would go high once the hard-stop was encountered? Am I simplifying this too much or could this approach work?

 

[masso-support]

we tried with clearpath motors and if I remember correctly the issue was that even if the motor failed to home then with HLFB signal you can't distinguish if homing failed or succeeded.

 

[legacymachine]

I think that it would be possible to detect failure / success with some simple logic.

SUCCESS = Ignore the input(s) connected to HLFB when homing cycle begins then look for input low (motor is moving toward home), then input high (motor hits hard-stop), then input low (motor is moving away/off home), then input high (motor finishes move away/off home).

FAILURE = anything else