Weird E-stop Behavior With PMDX-411

[atom]

Having some behavior with the e-stop that is abnormal.

If Mach4 is enabled and I press the e-stop, M4 recognizes it and disables. After a second or two (with e-stop still depressed), M4 reads "E-stop cleared". This is confirmed by on the diagnostic screen which does not show the e-stop active.

The second odd scenario is if the e-stop is depressed before powering on the system, both the PMDX-126 and M4 do not see the e-stop triggered.

System Information:
PMDX-411 connected to PMDX-126. (Normally a G540 is connected to the 126 but I disconnected to simplify the troubleshooting)
Mach4 4.2.0.2914 Build 2914 running on XP x86
External E-stop switch is only connected to the PMDX-126.
Input E-stop signal is enabled to the SmartBOBUSB on port 10 with "X" in Active Low.

Thanks-

Adam

[atom]

Right before I posted the question I figured out the issue, but wanted to go ahead and put it out here for reference.

The issue was a faulty e-stop switch. There was about 1/16 inch of play when the button was depressed. One of the two switches was not breaking the circuit unless the switch was pushed past that 1/16 inch of play. This explains the behavior since pressing the e-stop would momentarily break the circuit until the minor spring-back.

Moral of the story is don't skimp on the import stuff. $6 e-stop switch could have caused quite the mess later down the road.

Adam

[Steve Stallings]

E-Stop switches are one place where it is really important to use
quality parts. We have seen similar behavior with some of the
low cost switches offered on eBay. We even saw one unit with
two switch modules and it would latch with one switch activated
and the other one not activated.