Amp fault setup... joint.X.amp-fault-in

Hi,
I'm trying to set up the amp faults and have one little issue.
My custom.HAL has this:

# --- X drive ALM ---
net x-fault => joint.0.amp-fault-in <= hm2_7i76e.0.7i76.0.0.input-16-not

# --- Y drive ALM ---
net y-fault => joint.1.amp-fault-in <= hm2_7i76e.0.7i76.0.0.input-17-not

# --- Z drive ALM ---
net z-fault => joint.2.amp-fault-in <= hm2_7i76e.0.7i76.0.0.input-18-not

...and it works fine to stop the machine and produce an error message. What I'd like to change is the reset. After rebooting the amp(s) and clearing the fault, Linuxcnc holds onto the fault condition (gmoccapy), and the machine won't turn on. I need to close and restart lcnc.

Thanks in advance.

It just occurred to me, would this just be normal operation since the amp(s) have to be reset there's no way to know if the HOME and ZERO positions are still accurate?

I've had problems in the past with stepper drives 'jumping' when re-enabled or re-energized.  I've not seen a servo jump when re-enabled, but my philosophy is that without absolute encoders any amp/drive fault requires rehoming.

So if something on my machine triggers a fault (VFD, axis drives) I disable everything with the estop (bus power off) and then reset and re-home.

I think that is normal behaviour. I had to close and restart.
I think it's considered a catastrophic error.

I'm using stepperonline CL57Y & CL867Y stepper drivers. On fault an opto-isolated NPN transistor is enabled (or disabled depending on setup) which toggles a GPIO pin on the 7i76e. Upon reset the signal to the Mesa card goes away, but lcnc (gmoccapy?) doesn't seem to recheck the GPIO to see if the input is still active. Maybe this is by design, I don't know. It seems a no-brainer that the axis should be re-homed after the amp fault anyway. It would just be handy to do it without closing and restarting. It's no big deal to me. I was just wondering of I was missing something.

tommylight wrote:

I use Axis GUI/PlasmaC, i never had to close, just enable and move on.
This is a stepper system with LAM Technologies drives, they have no "reset" input, just disable (taken care by LinuxCNC on fault), enable.

The lams have a fault output which can be connected to amp-fault-in
I have seen it trigger if the drive overheats or the motor overheats when pushing to the extremes. Note it can take time for things to cool down before it can be reset.

Proper mounting per Lams specs generally solves the drive overheat.
The step boost function to 30% to 50% of desired current when at constant velocity  keeps things cool and eliminates motor faults.

Without the amp-fault-in, I had some massive lost steps and racked gantries when the drives  got hot. 
Reducing the current is quite safe becasue the drive is only working when accellerating and at constant velocity, the required current might only be 12% of the peak current. 

The Stepperonline Y-series drives do not have a reset function which can be activated by an external input.  They must be power-cycled to recover from a fault.

If they are connected to a WinPC via a serial connection, the 'tuning' software can reset a fault condition.  But that's not really helpful - or available - when using then under LCNC.

I use air-quotes around 'tuning' because it's likely the worst bit of software I've come across - as is the usb-serial dongle needed to connect to the drive.

The saving grace of the Y-series is that they can take 110VDC and so can drive steppers at extremely high speeds.  Plus they're cheap.

To be fair, I don't think you were running at 5 to 8 m/sec/sec acceleration. I really smashed them hard to see what they were capable of then backed off. It was amazing how much further you could push them with the step boost feature. Once a 120 amp plasma cutter overheated when just cutting at 40 amps without the drives or motors overheating, I figured I had tuned them!