My 7i76e Connection Sheet

A resistor would be needed only if the optocoupler common was ground
if the optocoupler can supply 24V to an input an pullup resistor is not needed

2K 1/2 W should be fine if a pullup is needed

A flipflop component with its clock driven by the alarm signal
(and data pin tied to '1') can detect the alarm signal

A better choice might be the oneshot component set for a bit over 1/2 second
The oneshot component has the advantage that it can be set up to trigger
on both edges of the alarm signal and may not require resetting

The optos are connected internally to a common ground.

I’ll look into the one shot as well.

Once again thanks for your help.

the mesa 7i76 e had 2 mpg inputs  can you add 2 more  ?

More could be added to either of the parallel expansion ports
(or a 7I73 could be added to the serial expansion port, adding 4 more MPG channels)

can i find somewhere an example how to setup a gearbox in the hal file
i have 4 speed settings combined 16 gears
28 35 45 56 70 90 112 140 180 224 280 355 450 560 700 900 rpm
i will us use a vfd to control the motor 1450rpm 7.5kw

Great, thanks a lot for sharing this!