PMDX 424 E-Stop & Fault actions... similar to PMDX 126?

[bru102]

Drinking in Manuals and Forum posts! The PMDX 126 BOB manual provides some great detail on input actions and filtering in section 6 that I can't seem to find in the 4xx SmartBOB manuals. I'm wondering if the 424 acts similarly, particularly on E-Stop and Fault.  Please point me elsewhere if I'm missing something! 

A couple specific questions on the 424:
 
  1. Is Fault filtered and captured after ~50ms as with the 126, and is that when all outputs (incl. motor enables) are disabled AND Mach4 gets the report?
  2. Are (a) outputs re-enabled on-board if Fault is de-asserted, or (b) does the 424 wait for Mach4 to restart things?
  3. If 2(a) is true, is there any concern about, say, an unintended spindle restart or axis movement, independent of Mach?

Thanks in advance... This will help me design the interface between the PMD 424 Fault input and my 3 servo Fault Outputs.

Ray

[Steve Stallings]

On the PMDX-424 the Fault input and the E-Stop input are electrically combined into a single signal and the resulting signal is filtered with a 50 milliSecond time constant. A single event greater that 50 milliSeconds will trigger an E-Stop, but so will three 30 milliSecond events over a 100 milliSecond interval.

Once the EStop input causes the SmartBOB to disable its outputs, they remain disabled until:

(1) The ~Fault/EStop inputs are no longer active

**AND**

(2) The operator clicks on the "Enable" button in Mach4.

If the EStop input is still asserted, the PMDX-424 will force Mach4 to remain disabled.  This pertains to all of our SmartBOB products.  All of them require the operator to enable Mach4 in order to enable any of the SmartBOB's outputs.

[bru102]

Great explanation, thanks Steve!  It make sense for safety, and it seems like PMDX makes E-Stop and /Fault connections as straight forward as possible. 

I just need a little logic to invert the upside-down Fault signal from ClearPath motors,  and fix the issue that ClearPath also asserts Fault any time a motor is not enabled (which would keep PMDX & Mach in E-Stop forever). 

Kudos: This would be more complicated without PMDX E-stop/Fault 50ms filtering? Otherwise sequential logic would be needed to eliminate ?runt? Fault pulses due to the delay between Enable and HLFB signals.

I??ll clean up my schematic for this circuit and post it? may be useful to somebody else using ClearPath servos.

Ray

[MikekiM]

Could someone please show me how I would use the e-bay MOSFET board with HLFB circuit of 4 clearpath motors and the fault input on the PMDX -126? A schematic would be great. Thank You, Mikw