E-Stop input problem

[eurikain]

Hello,

I am running the first few tests with my control cabinet. I am able to move all axis in the correct direction and required speed. I am not trying to set up the e-stop, but it won't want to work !

Here is my wiring diagram:



And here is the Mach3 setup I've got:
E-STOP port #1, pin number 12, active low

When the master relay is off, there is now power going to the drivers / motors, but the BOB, 24V and 5V power supplies are powered. Thus, Mach3 should consider that the estop is pressed (since it's "active low") and not let me press the "reset" button on the screen. However, it lets me click the reset button fine.. so it doesn't recognise the E-Stop..

I checked the e-stop circuit was connected to pin 12 of the BOB, and it is. I also checked with a ohm meter that the e-stop circuit closes and opens in accordance with the master relay, and it does: master relay off, now resistance through the loop; master relay on, resistance goes through the loop. However, if I measure the voltage in the loop, I reads 0V no matter if it is closed or open. Would the BOB be responsible for this ?

All the best,
G.