Not sure how that is going to work, but I have to say that on my own machine, the fault/alarm signals go to a safety relay and not directly to the CSMIO. However, you don't need to use three inputs - you can wire the alarm signals in series, and take them to a single input. The AM882 can be configured to be active high or low on a fault; again, I'm not using exactly the same hardware as I have EM806 which are, in effect, a slightly later version of the AM882, so I'm not sure exactly how they are configured fresh from the factory. Looking at the extract of the manual above, you just need to take +24V to the + alarm connection on the first driver, take its - connection to the + on the next, and so on. When all are connected in series, take a wire from the - alarm connection on the last one to one input on the CSMIO. Then, in Mach3, you can use this as the "alarm" signal (can't remember what it's actually called, but it's something like that). In my case, because I want a stall alarm signal to act as an e-stop, I also connect my three e-stop switches in series with the alarm signals as well; a "fault" from any of them will then activate the e-stop actions.