Looking for some validation of my estop circuit as I didn't need to build one on my last machine, it was all integrated into the servo BOB.

My proposed circuit is a normal start-stop relay circuit with the addition of the EM806 fault signals, is this how everyone else does it?

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E-stop is NC
Reset is NO momentary
FLT 1-4 are the open collector FLT outputs from the 4xEM806.
K1 is a DPST relay, first pole used for latching, second pole to switch contactor.
K2 is a SPDT relay using the NC contact

Functions as follows:
With no driver fault signals K2 is off and conducting.
E-stop is conducting and in series with K2.
K1 is off.
Reset is pressed momentarily, current flows through K1 coil, latching K1 on.

Now if any driver fault signal switches on, K2 swiches on breaking the path through K1 coil, K1 switches off. If fault clears K1 remains off until reset is pressed.
Similarly if E-stop is pressed this also breaks the path through K1 coil and the same happens.

Any additional NO sources of fault can be paralleled with the FLT outputs. Any other NC sources of fault can be added in series with E-stop + K2.

Thoughts?