A difference between the GC-100-12 and GC-100-18 is the number of "expansion slots"... Yet global cache nor any of its distributors seem to make any mention of these expansion products being available for sale... is this a future item?
If I want more than 6 contact closure sensors today, is the best thing to buy multiple GC-100 units?
I am using a MDT Automation BE-04001.01 4-port contact closure in my KNX installation for contact closure input. It is around <15EUR per contact closure input, and for me works flawless
Thanks for your reply. I should have mentioned I'm in North America - so I don't think KNX/EIB is an option for me unfortuntately.
Well KNX does exist in North America as well, even in the US, and that sensor is usable world wide. In addition to the KNX stuff, Merten has a similar thingie for Z-Wave, so I am pretty sure, you should be able to find something in the home automation 3rd world, better known as the US of A.